Jeep Cherokee 1994 User Manual

J LUBRICATION AND MAINTENANCE 0 - 1

LUBRICATION AND MAINTENANCE

CONTENTS

page page

CHASSIS AND BODY COMPONENTS ....... 30

DRIVETRAIN ........................... 22

ENGINE MAINTENANCE .................. 13

GENERAL INFORMATION

INDEX

page page

Classification of Lubricants ..................2

Components Requiring No Lubrication .......... 3

Fluid Capacities .......................... 4

Fuel Requirements ........................ 2

INTRODUCTION

Jeept lubrication and maintenance is divided into

required and recommended service tasks.

The recommendations and procedures listed in this

group are intended for Jeept Dealer Service Personnel.

Because conditions vary, it is necessary to schedule
service tasks according to a time interval as well as a
distance interval.

It is the owner’s responsibility to have vehicle ser­viced. Owner is to pay for labor and necessary parts
that are not covered by the warranty.

Additional lubrication and maintenance informa­tion is listed in the Owner’s Manual, which is in­cluded with the vehicle.

SEVERE DRIVING CONDITIONS

When a vehicle is subjected to a severe driving con­dition, time between recommended maintenance
should be decreased.

Refer to Engine Maintenance for the engine oil and
filter maintenance interval when involved with a se­vere driving condition.

A severe driving condition is defined as either:

• frequent short trip driving less than 24 km (15
miles);

• frequent driving in a dusty environment;

• trailer towing;

• extensive engine idling;

• sustained high-speed operation;

• desert operation;

• frequent starting and stopping;

GENERAL INFORMATION .................. 1

JUMP STARTING, HOISTING AND TOWING .. 7

MAINTENANCE SCHEDULES ............... 5

Introduction .............................. 1

Recommended Lubricant and Replacement Parts . 3

Routine Service ........................... 2

• cold-climate operation;

• off-road driving; or

• commercial service.

To service a Jeept vehicle for a severe driving con-

dition, change all the lubricating fluids and lubricate:

• the body components,

• all the driveline coupling joints, and

• the steering linkage

more often than for a normal driving condition to

prevent excessive wear of the components.

DUSTY AREAS

Driving in an area with dust-filled air increases the
risk of particles entering the engine and crankcase.
With this type of severe driving condition, attention
should be given to the engine and crankcase compo­nents.

OFF-ROAD (4WD) OPERATION

After completion of off-road (4WD) operation, the
underside of the vehicle should be thoroughly in­spected. Examine threaded fasteners for looseness.

HARSH SURFACE ENVIRONMENTS

After vehicle operation in a harsh surface environ­ment, the following components should be inspected
and cleaned as soon as possible:

• brake drums,

• brake linings,

• front wheel bearings (2WD vehicles only), and

• axle coupling joints.

This will prevent wear and/or unpredictable brake
action.

0 - 2 LUBRICATION AND MAINTENANCE J

ROUTINE SERVICE

The following routine vehicle service is highly rec-

ommended on a monthly basis.

TIRES—Inspect the tires for unusual wear/damage
and determine if the inflation pressure is acceptable
for the vehicle load.

BATTERY—Inspect and clean the terminals.
Tighten the terminals, if necessary.

FLUIDS—Determine if the coolant, brake fluid,
power steering, automatic transmission, and clutch
fluid level are acceptable. Add fluid, if necessary.

LIGHTS/ELECTRICAL—Test all the electrically
operated systems in the vehicle for proper operation.

It is also recommended that the engine oil level
and the windshield washer fluid level be deter­mined (and corrected) during each fuel fill-up.

FUEL REQUIREMENTS

All Jeept engines require the use of unleaded gas­oline. In addition, the fuel must have a minimum oc­tane rating of 87.

CAUTION: UNLEADED FUEL ONLY must be used in
vehicles equipped with a catalyst emission control
system. All vehicles have reminders printed on the
instrument panel (Fig. 1) and on the fuel filler door
(Fig. 2). Vehicles also have fuel filler tubes that are
designed to accept only the small-diameter un­leaded gasoline nozzles. It is illegal to defeat the
design of an unleaded fuel filler tube.

Fig. 2 Unleaded Fuel Only Reminder—Fuel Filler

Door

• American Petroleum Institute (API), and

• National Lubricating Grease Institute (NLGI).

ENGINE OIL

SAE VISCOSITY GRADE

An SAE viscosity grade is used to specify viscosity
of engine oil. SAE 30 specifies a single viscosity en­gine oil. Engine oils also have multiple viscosities
(Fig. 3).

CLASSIFICATION OF LUBRICANTS

Lubricating fluids and chassis component lubri­cants are classified and graded according to stan­dards recommended by the:

• Society of Automotive Engineers (SAE),

Fig. 1 Unleaded Fuel Only Reminders—Fuel Gauge

Fig. 3 SAE Oil Viscosity Grade & API Service Grade

The viscosity grade of an oil is an indicator of its
thickness or flow capability. The lower the number,
the better the flow. The second viscosity grade num­ber (without a W suffix) is the warm/hot-temperature
viscosity. The viscosity increases with engine temper­ature. With a single viscosity grade, the oil viscosity
is valid only for one narrow temperature range.

J LUBRICATION AND MAINTENANCE 0 - 3

Above that temperature range the viscosity will de­crease, and below that range the viscosity will in­crease.

An engine oil with an SAE 5W-30 viscosity grade
provides good flow capability for fast cold weather
engine starts. The viscosity will then increase with
engine temperature to provide good high-tempera­ture engine lubrication.

API SERVICE GRADE

The API Service Grade specifies the type of engine/
operating conditions for which the oil is intended.
The API Service Grade specifications also apply to
energy conserving engine oils (Fig. 3). The API cer­tification mark is also used indicating that the oil is
certified to meet the most critical requirements es­tablished by the manufacturer (Fig. 4).

CHASSIS COMPONENT AND WHEEL BEARING
LUBRICANTS

The chassis component and wheel bearing lubri­cants are identified by the NLGI Certification Sym­bol (Fig. 5).

Fig. 5 NLGI Lubricant Certification/Identification

Symbol

The letter G indicates wheel bearing lubricant and
the letter L indicates chassis lubricant. When the
letters are combined the lubricant can be used for
dual applications. The suffix letters C and B indi­cates quality level of the lubricant. Use only lubri­cants that display the NLGI Certification Symbol.

Fig. 4 The API Engine Oil Certification Mark

For maximum protection, use API Service Grade

SG, SG/CD or SG/CE engine oil in Jeept engines.

GEAR LUBRICANTS

A dual SAE viscosity grade is also used to specify

the viscosity of multipurpose gear lubricants.

The API lubrication quality grade designation
identifies gear lubricants in terms of recommended
usage.

RECOMMENDED LUBRICANT AND REPLACEMENT
PARTS

Jeept vehicles are engineered to provide many

years of dependable operation. When necessary, MO-

PAR brand lubricants and genuine replacement
parts are highly recommended.

COMPONENTS REQUIRING NO LUBRICATION

There are many components that should not be lu­bricated. The components that should not be lubri­cated are:

• air pumps;

• generator bearings;

• drive belts;

• drive belt idler pulleys;

• rubber bushings;

• starter motor bearings;

• suspension strut bearings;

• throttle control cables;

• throttle linkage ball joints; and

• water pump bearings.

0 - 4 LUBRICATION AND MAINTENANCE J

FLUID CAPACITIES

J LUBRICATION AND MAINTENANCE 0 - 5

MAINTENANCE SCHEDULES

INTRODUCTION

Chrysler Corporation has compiled recommended
lubrication and maintenance schedules and proce­dures to help reduce premature wear or failure over
a broad range of operating conditions.

SEVERE SERVICE MAINTENANCE

If the vehicle is involved with a severe driving con­dition, after each 4 800-km (3,000-miles)/3-month in­terval. A severe driving condition includes:

• frequent short trip driving less than 24 km (15
miles);

• frequent driving in a dusty environment;

• trailer towing;

• extensive engine idling;

• sustained high-speed operation;

• desert operation;

• frequent starting and stopping;

• cold-climate operation;

• off-road driving; or

• commercial service.

MAINTENANCE SCHEDULES

AT EACH STOP FOR FUEL

• Check engine oil level, add as required.

•

Check windshield washer solvent and add if required.

• Check fluid level in battery.

• Rotate Tires.

22,500 MILES (36 000 KM) OR AT 18 MONTHS

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Rotate Tires.

30,000 MILES (48 000 KM) OR AT 24 MONTHS

• Replace air cleaner filter.

• Replace spark plugs.

• Adjust drive belt.

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Check fluid level in battery.

• Drain and refill automatic transmission.

• Drain and refill transfer case.

• Rotate Tires.

ONCE A MONTH

• Check tire pressure and look for unusual wear or
damage.

• Inspect battery and clean and tighten terminals as
required.

• Check electrolyte level and add water as needed.

• Check fluid levels of coolant reservoir, power steer-

ing and transmission and add as needed.

• Check all lights and all other electrical items for
correct operation.

• Check rubber seals on each side of the radiator for
proper fit.

7,500 MILES (12 000 KM) OR AT 6 MONTHS

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Rotate Tires.

15,000 MILES (24 000 KM) OR AT 12 MONTHS

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

37,500 MILES (60 000 KM) OR AT 30 MONTHS

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Drain and refill manual transmission.

• Rotate Tires.

45,000 MILES (72 500 KM) OR AT 36 MONTHS

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Check fluid level in battery.

• Rotate Tires.

52,500 MILES (84 500 KM) OR AT 42 MONTHS

• Flush and replace engine coolant.

• Check engine coolant system hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Rotate Tires.

0 - 6 LUBRICATION AND MAINTENANCE J

60,000 MILES (96 500 KM) OR AT 48 MONTHS.

• Replace air cleaner filter.

• Replace distributor cap and rotor.

• Replace ignition wires.

• Replace spark plugs.

• Adjust or replace drive belt.

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Replace fuel filter (not required for Calif. vehicles).

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Check fluid level in battery.

• Drain and refill automatic transmission.

• Drain and refill transfer case.

• Rotate Tires.

67,500 MILES (108 500 KM) OR AT 54
MONTHS

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Rotate Tires.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Check fluid level in battery.

• Drain and refill automatic transmission.

• Drain and refill transfer case.

• Rotate Tires.

97,500 MILES (157 000 KM) OR AT 78
MONTHS

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Rotate Tires.

105,000 MILES (169 000 KM) OR AT 84
MONTHS

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Rotate Tires.

75,000 MILES (120 500 KM) OR AT 60
MONTHS

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Drain and refill manual transmission.

• Rotate Tires.

82,500 MILES (133 000 KM) OR AT 66
MONTHS

• Flush and replace engine coolant.

• Check engine coolant system, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Rotate Tires.

90,000 MILES (145 000 KM) OR AT 72
MONTHS

• Replace air cleaner filter.

• Replace spark plugs.

• Adjust drive belt.

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

112,500 MILES (181 000 KM) OR AT 90
MONTHS

• Flush and replace engine coolant.

• Check engine coolant system hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Rotate Tires.

120,000 MILES (193 000 KM) OR AT 96
MONTHS

• Replace air cleaner filter.

• Replace distributor cap and rotor.

• Replace ignition wires.

• Replace spark plugs.

• Adjust or replace drive belt.

• Check engine coolant level, hoses and clamps.

• Change engine oil.

• Replace engine oil filter.

• Check exhaust system.

• Replace fuel filter (not required for Calif. vehicles).

• Lubricate steering linkage (4x4 models).

• Lubricate propeller shaft universal joints.

• Check fluid level in battery.

• Drain and refill automatic transmission.

• Drain and refill transfer case.

• Rotate Tires.

J LUBRICATION AND MAINTENANCE 0 - 7

JUMP STARTING, HOISTING AND TOWING

JUMP STARTING

WARNING: DO NOT ATTEMPT TO PUSH OR TOW A
VEHICLE TO START THE ENGINE. UNBURNED
FUEL COULD ENTER THE EXHAUST CATALYTIC
CONVERTER AND IGNITE AFTER THE ENGINE IS
STARTED. THIS COULD CAUSE THE CONVERTER
TO OVERHEAT AND RUPTURE.

BOOSTER BATTERY

WARNING: TO PREVENT PERSONAL INJURY OR
CLOTHING DAMAGE, DO NOT ALLOW BATTERY
(ACID) TO CONTACT EYES, SKIN OR CLOTHING.
DO NOT LEAN OVER A BATTERY WHEN CON­NECTING JUMPER CABLES. DO NOT ALLOW THE
POSITIVE AND NEGATIVE CABLE CONNECTOR
CLAMPS TO CONTACT EACH OTHER. KEEP OPEN
FLAMES AND SPARKS AWAY FROM THE BATTERY
VENT HOLES. ALWAYS WEAR EYE PROTECTION
WHEN INVOLVED WITH BATTERIES.

Fig. 6 Jumper Cable Connections

If it is necessary to use a booster battery and
jumper cables to start an engine use the following
procedure.

(1) Engage the parking brake and shift the auto­matic transmission to PARK, manual transmission
shift to NEUTRAL.

(2) Turn off all lights, the heater-A/C blower mo­tor, and all other electrical loads.

WARNING: WHEN THE AIR TEMPERATURE IS BE­LOW THE FREEZING POINT (0°C OR 32°F), THE
ACID IN A DISCHARGED VEHICLE BATTERY CAN
FREEZE. DO NOT ATTEMPT TO JUMP START AN
ENGINE BEFORE DETERMINING THE CONDITION
OF THE BATTERY.

(3) Inspect the general condition of the battery.

CAUTION: Do not permit metal surfaces on vehicles
to contact because this could establish ground con­tinuity between vehicle bodies.

WARNING: DO NOT CONNECT A JUMPER CABLE
CONNECTOR CLAMP TO THE NEGATIVE POST OF
THE DISCHARGED BATTERY.

(5) Connect a black jumper cable connector clamp
to the negative (-) terminal on the booster battery.
Connect the other black jumper cable connector
clamp to a good ground.

(6) Start the engine.

WARNING: THE USE OF ANY JUMPER CABLE DIS­CONNECTION PROCEDURE OTHER THAN THAT
DESCRIBED BELOW COULD RESULT IN:

• PERSONAL INJURY CAUSED BY BATTERY
ELECTROLYTE SQUIRTING FROM THE BATTERY
VENTS.

• PERSONAL INJURY AND/OR PROPERTY DAM­AGE CAUSED BY BATTERY EXPLOSION.

• DAMAGE TO THE BOOSTER VEHICLE OR THE
DISABLED VEHICLE CHARGING SYSTEM.

(4) Attach a red cable connector clamp to the pos­itive (+) terminal on the booster battery. Connect
the other red cable connector clamp to the positive
(+) terminal on the discharged battery (Fig. 6).

CAUTION: Use care to avoid allowing the positive
(+) and negative (-) cable clamps to contact each
other. DO NOT lean over the battery when connect­ing the cable clamps.

(7) After the engine is started, or if the engine
fails to start, the jumper cables must be disconnected
in the following order:

• Black (negative) cable connector clamp from the
engine ground contact.

• Black (negative) cable connector clamp from the
negative terminal (-) on the booster battery.

• Red (positive) cable connector clamps from the pos­itive (+) terminals on both batteries.

0 - 8 LUBRICATION AND MAINTENANCE J

PORTABLE STARTING UNIT

There are many types of portable starting units
available for starting engines. Follow the manufac­turer’s instructions when involved in any engine
starting procedure.

HOISTING RECOMMENDATIONS

FLOOR JACK

When properly positioned, a floor jack can be used
to lift a Jeept vehicle. Support the vehicle in the
raised position with jack stands at the front and rear
ends as applicable (Fig. 7).

HOIST

A Jeept vehicle can be lifted with a swiveling-arm
type hoist; with a wheel-lift, twin-post hoist; or with
a ramp-type, drive-on hoist.

When a swiveling-arm, frame-contact type
hoist is used, ensure that the lifting pads are po­sitioned at the correct sub frame rail (Fig. 7).

TOWING RECOMMENDATIONS

TOWING EQUIPMENT

A vehicle equipped with SAE approved sling-type
towing equipment can be used to tow all Jeept vehi­cles (Fig. 8). When it is necessary to rear-tow a vehi­cle, use the wheel-lift towing method with a tow
dolly located under the front wheels. A vehicle with
flat-bed towing equipment can also be used to trans­port a disabled vehicle.

Fig. 7 Correct Vehicle Lifting Locations—Typical

CAUTION: Do not attempt to lift a JeepT vehicle
with a floor jack positioned under:

• an axle tube,

• a body side sill,

• a steering linkage component,

• a drive shaft,

• the engine or transmission oil pan,

• the fuel tank, or

• a front suspension arm.

Use the correct sub-frame rail or frame rail

lifting locations only (Fig. 7).

Fig. 8 Tow Vehicles With Approved Equipment

A wooden crossbeam with spacer blocks could pos­sibly be required for proper connection when using
the sling-type, front-end towing method (Fig. 9).

Fig. 9 Crossbeam & Spacer Block Construction

SAFETY PRECAUTIONS

The following safety precautions must be consid­ered when preparing for and during a vehicle towing
operation:

J LUBRICATION AND MAINTENANCE 0 - 9

• if the vehicle is damaged, secure the loose and pro­truding parts;

• always use a safety chain system that is indepen­dent of the lifting and towing equipment;

• do not allow any of the towing equipment to con­tact the disabled vehicle’s fuel tank;

• do not allow anyone to be under the disabled vehi­cle while it is lifted by the towing equipment;

• do not allow passengers to ride in a vehicle being
towed;

• always observe all state and local laws involving
warning signals, night illumination, speed, etc.

• do not attempt a towing operation that could jeop­ardize the safety of the operator, bystanders or other
motorists;

• do not exceed a towing speed of 48 km/h (30 mph);

• avoid towing distances of more than 24 km (15

miles) whenever possible; and

• do not attach tow chains or a tow sling to a
bumper, the steering linkage, the universal joints,
the constant velocity (CV) joints, or a drive shaft.

Fig. 10 Sling-Type, Front-End Towing (XJ Front

View)

CLEARANCES AND RAMP ANGLE

SURFACE CLEARANCE

The end of the disabled vehicle that is attached to
the tow vehicle should be lifted a minimum of 10 cm
or four inches off the surface. Inspect to ensure that
the opposite end of the disabled vehicle has clearance
from the surface.

RAMP ANGLE—FLAT-BED TOWING

If a vehicle with flat-bed towing equipment is used,
the approach ramp angle should not exceed 15 de­grees.

SLING-TYPE, FRONT-END TOWING

XJ VEHICLES

Use the following guidelines when the tow vehicle
is attached to the front end of a disabled vehicle.

(1) Always tow with the front wheels lifted off the
surface and turned all the way to the right.

(2) Attach a J-hook to the disabled vehicle at the
left side of the axle (Fig. 10).

(3) Position the sling crossbar close to the J-hook
and below the front bumper (Fig. 11).

(4) Secure a chain to the right side of vehicle by
placing it over the axle shaft tube and attaching it to
a structural member.

(5) Attach the safety chains to the vehicle.

2WD With Manual Or Automatic Transmission

(6) Turn the ignition switch to the OFF position to
unlock the steering wheel.

(7) Shift the transmission to NEUTRAL, mark the
drive shaft and axle drive pinion gear shaft yoke for
installation reference. Remove the drive shaft from
the vehicle.

Fig. 11 Sling-Type, Front-End Towing (XJ Rear

View)

(8) Cover the exposed end of the transmission ex­tension housing and the universal joints. Store the
drive shaft in a safe place.

4WD, Command-Trac (231 Part-Time 4WD
Transfer Case) And Manual Transmission

(6) Turn the ignition switch to the OFF position to
unlock the steering wheel.

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(7) Shift the manual transmission into a forward
gear and the transfer case to NEUTRAL.

4WD, Command-Trac (231 Part-Time 4WD
Transfer Case) And Automatic Transmission

(6) Turn the ignition switch to the OFF position to
unlock the steering wheel.

0 - 10 LUBRICATION AND MAINTENANCE J

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(7) Shift the automatic transmission to PARK and
the transfer case to NEUTRAL.

4WD, Selec-Trac (242 Full-Time 4WD Transfer
Case) And Automatic Transmission

(6) Turn the ignition switch to the OFF position to
unlock the steering wheel.

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(7) Shift the automatic transmission to PARK and
the transfer case to NEUTRAL.

YJ VEHICLES

Use the following guidelines when the tow vehicle
is attached to the front of a disabled vehicle.

(1) Always tow with the front wheels lifted off the
surface and turned all the way to the right.

CAUTION: Use tow chains with T-hooks for con­necting to the disabled vehicle’s frame rails (Fig.

12). Never use J-hooks.

Fig. 13 Sling-Type, Front-End Towing (YJ Vehicles)

Command-Trac (231 Part-Time 4WD Transfer

Case) And Automatic Transmission

(6) Turn the ignition switch to the OFF position to

unlock the steering wheel.

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(7) Shift the automatic transmission to PARK and
the transfer case to NEUTRAL.

Fig. 12 Tow Chains & Hooks

(2) Attach the T-hooks to the slots in the front end

of each frame rail (Fig. 13).

(3) Position each safety chain over the top of each

front spring and inboard of each front spring shackle.

(4) Double wrap each chain.
(5) Position the sling crossbar under the front

bumper.

Command-Trac (231 Part-Time 4WD Transfer

Case) And Manual Transmission

(6) Turn the ignition switch to the OFF position to

unlock the steering wheel.

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(7) Shift the manual transmission to a forward
gear and the transfer case to NEUTRAL.

SLING-TYPE, REAR-END TOWING

YJ VEHICLES—Use wheel-lift equipment ONLY
when towing from the rear end of the vehicle is nec­essary.

XJ VEHICLES—Use the following guidelines
when the tow vehicle is attached to the rear of the
disabled vehicle.

(1) Attach J-hooks around the axle shaft tubes out­board of the shock absorber.

(2) Place the sling crossbar under and forward of
the bumper.

(3) Attach safety chains around the frame rails.

2WD With Manual Or Automatic Transmission

(1) Attach J-hooks around the axle shaft tubes out­board of the shock absorber.

(2) Place the sling crossbar under and forward of
the bumper.

(3) Attach safety chains around the frame rails.

(4) Turn the ignition switch to the OFF position to
unlock the steering wheel.

(5) Clamp the steering wheel with the front wheels
in the straight ahead position. Do not use the steer­ing column lock as a substitute for a clamping de­vice.

(6) Shift the transmission to NEUTRAL.

J LUBRICATION AND MAINTENANCE 0 - 11

4WD, Command-Trac (231 Part-Time 4WD

Transfer Case) And Manual Transmission

(1) Attach J-hooks around the axle shaft tubes out-

board of the shock absorber.

(2) Place the sling crossbar under and forward of

the bumper.

(3) Attach safety chains around the frame rails.
(4) Turn the ignition switch to the OFF position to

unlock the steering column.

(5) Clamp the steering wheel with the front wheels
in the straight ahead position. Do not use the steer­ing column lock as a substitute for a clamping de­vice.

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(6) Shift the transmission to a forward gear and
the transfer case to NEUTRAL.

4WD, Command-Trac (231 Part-Time 4WD
Transfer Case) And Automatic Transmission

(1) Attach J-hooks around the axle shaft tubes out­board of the shock absorber.

(2) Place the sling crossbar under and forward of
the bumper.

(3) Attach safety chains around the frame rails.

(4) Turn the ignition switch to the OFF position to
unlock the steering column.

(5) Clamp the steering wheel with the front wheels
in the straight ahead position. Do not use the steer­ing column lock as a substitute for a clamping de­vice.

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(6) Shift the transmission to PARK and the trans­fer case to NEUTRAL.

4WD, Selec-Trac (242 Full-Time 4WD Transfer
Case) And Automatic Transmission

(1) Attach J-hooks around the axle shaft tubes out­board of the shock absorber.

(2) Place the sling crossbar under and forward of
the bumper.

(3) Attach safety chains around the frame rails.

(4) Turn the ignition switch to the OFF position to
unlock the steering column.

(5) Clamp the steering wheel with the front wheels
in the straight ahead position. Do not use the steer­ing column lock as a substitute for a clamping de­vice.

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(6) Shift the transmission to PARK and the trans­fer case to NEUTRAL.

TOWING WHEN IGNITION KEYS ARE NOT
AVAILABLE

VEHICLE DOORS UNLOCKED

2WD Vehicles

Either one of two methods can be used:

• tow the vehicle with the drive shaft removed (refer
to Sling-Type, Front-End Towing); or

• place a tow dolly under the rear wheels (Fig. 14)
and tow with the front end raised (refer to Sling­Type, Front-End Towing).

Fig. 14 Sling-Type, Front-End Towing With Rear

Wheels On A Tow Dolly

4WD, Command-Trac (231 Part-Time 4WD

Transfer Case) And Manual Transmission

(1) Shift the manual transmission to a forward

gear.

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(2) Shift the transfer case to NEUTRAL.

(3) The vehicle can now be towed with the front
wheels raised (refer to Sling-Type, Front-End Tow­ing).

4WD, Command-Trac (231 Part-Time 4WD
Transfer Case) And Automatic Transmission

(1) Check and ensure that the automatic transmis­sion is in PARK.

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(2) Shift the transfer case to NEUTRAL.

(3) The vehicle can now be towed with the front
wheels raised (refer to Sling-Type, Front-End Tow­ing).

4WD, Selec-Trac (242 Full-Time 4WD Transfer
Case) And Automatic Transmission

(1) Check and ensure that the automatic transmis­sion is in PARK.

0 - 12 LUBRICATION AND MAINTENANCE J

When the transfer case is in the NEUTRAL po­sition, both axles are disengaged from the pow­ertrain. This allows the vehicle to be towed
without removing the drive shafts.

(2) Shift the transfer case to NEUTRAL.

(3) The vehicle can now be towed with the front
wheels raised (refer to Sling-Type, Front-End Tow­ing).

VEHICLE DOORS LOCKED

Place a tow dolly under the rear wheels (Fig. 14)
and tow with the front end raised (refer to Sling­Type, Front-End Towing).

4WD EMERGENCY TOWING—TRANSFER CASE
NOT SHIFTED TO NEUTRAL

When a situation arises and the transfer case can­not be shifted to NEUTRAL, any of the following
methods can be used to tow a 4WD vehicle.

Drive shafts not removed, place the rear
wheels on a tow dolly and tow with the front
end raised.

Drive shafts not removed, place the front
wheels on a tow dolly and tow with the rear end
raised.

Rear drive shaft removed, tow with the front
end raised.

Front drive shaft removed, tow with the rear
end raised.

Both drive shafts removed, tow with all four
wheels on the road surface.

(1) Turn ignition key switch to the unlocked (OFF)
position.

(2) Shift the transmission to the NEUTRAL posi­tion.

(3) Determine the method by which the vehicle
will be towed and prepare the vehicle for towing.

(4) Connect the vehicle to the tow vehicle. Refer to
the applicable procedure.

4WD VEHICLES

(1) Mark the drive shafts and the axle drive pinion

gear shaft yokes for installation alignment reference.

(2) Remove the drive shafts. Install a protective
covering over the drive shaft U-joints/CV-joints to re­tain them assembled and protected.

(3) Cover the exposed ends of the transfer case.

CAUTION: Whenever a drive shaft has been re­moved and installed, check the transmission fluid
level of the transmission and transfer case. Driving
a vehicle with low tranfer case fluid can damage the
transmission and transfer case.

EMERGENCY TOW HOOKS

WARNING: REMAIN AT A SAFE DISTANCE FROM A
VEHICLE THAT IS BEING TOWED VIA ITS TOW
HOOKS. THE TOW STRAPS/CHAINS COULD POSSI­BLY BREAK AND CAUSE SERIOUS INJURY.

Some Jeept vehicles are equipped with emergency
tow hooks located at the front end (Fig. 15). Some
Jeept vehicles also have emergency tow hooks lo­cated at the rear ende. The tow hooks should be used
for EMERGENCY purposes only.

CAUTION: DO NOT use emergency tow hooks for
tow truck hook-up or highway towing.

FLAT TOWING (4 TIRES/WHEELS ON
SURFACE)

Tow a vehicle in this manner only when all four
wheels will freely rotate. Prepare the vehicle accord­ing to the following procedures.

2WD VEHICLES

(1) Mark the drive shaft and the axle drive pinion
gear shaft yoke for installation alignment reference.

(2) Remove the drive shaft. Install a protective
covering over the drive shaft U-joints to retain them
assembled and protected.

(3) Cover the open end of the transmission exten­sion housing.

Fig. 15 Emergency Front Tow Hooks—XJ & YJ

Vehicles

J LUBRICATION AND MAINTENANCE 0 - 13

ENGINE MAINTENANCE

INDEX

page page

Accessory Drive Belt ...................... 20

Air-Conditioner Compressor/Hoses/Fittings ...... 21

Battery ................................ 18

Cooling System .......................... 16

Crankcase Ventilation System ............... 17

Engine Air Cleaner Filter Element ............ 16

Engine Break-In .........................13

Engine Oil .............................. 13

ENGINE BREAK-IN

After first starting a new engine, allow it to idle
and warm up for at least 15 seconds before shifting
the transmission into a drive gear.

Drive the vehicle at:

• varying speeds less than 80 km/h (50 mph) for the
first 160 km (100 miles), and

• speeds less than 88 km/h (55 mph) for the first 800
km (500 miles).

Avoid driving at full-throttle for extended periods
of time. Also, avoid fast acceleration and sudden
stops.

A special break-in engine oil is not required. The
original oil installed in a vehicle is a quality lubri­cant. There is no requirement to have the oil
changed or the oil filter replaced until the first
scheduled maintenance interval.

The engine oil, coolant and all the other engine re­lated fluid levels should be determined on a regular
basis.

ENGINE OIL

SPECIFICATIONS

Engine Oil Change and Filter Replacement ..... 15

Engine Oil Filter .........................14

Engine Supports ......................... 20

Exhaust System ......................... 20

Fuel Usage Statement—Gas Engines ......... 17

Ignition Cables, Distributor Cap and Rotor ...... 18

Rubber and Plastic Ducts/Hoses/Tubing .......19

Spark Plugs ............................ 18

Fig. 1 Temperature/Engine Oil Viscosity

ENERGY CONSERVING OIL

In selecting the correct API grade and SAE grade,
an ENERGY CONSERVING type engine oil is also
recommended.

CONTAINER IDENTIFICATION

Standard engine oil notations have been adopted
for selection of engine oil. The notations are located
on side of plastic bottles and on the top of engine oil
cans (Fig. 2).

API SERVICE GRADE

For maximum engine protection during all driving
conditions, install an engine oil that conforms to API
Service Grade. MOPAR Engine Oil conforms to all of
these API Service Grades.

SAE VISCOSITY

SAE designated multi-viscosity grade engine oil is
to protect engines. This type of engine oil can usually
be installed and remain in the engine until the next
scheduled oil change. Select the engine oil viscosity
according to the lowest ambient air temperature ex­pected before the next scheduled oil change (Fig.1).
Low viscosity engine oil allows easier engine starting
during cold weather. SAE 5W-30 viscosity engine oil
is recommended when the ambient air temperatures
consistently decrease to below 10°F (-12°C).

Fig. 2 Engine Oil Container Standard Notations

• The top, outer field contains the API Service
Grade notation for the engine oil.

0 - 14 LUBRICATION AND MAINTENANCE J

• The center field contains the SAE viscosity
grade notation for the engine oil.

• The lower, outer field contains either the EN-
ERGY CONSERVING or the ENERGY CON­SERVING II notation for the engine oil.

CAUTION: Non-detergent engine oil or straight-min­eral oil must never be used to lubricate a JeepT en­gine. These type of oils will not provide proper
engine lubrication and can result in engine damage.

LEVEL INDICATOR (DIPSTICK)

The engine oil level indicator is located at the right
rear of both 2.5L engines and 4.0L engines (Fig. 3).

Fig. 4 Engine Oil Dipstick—2.5L Engine

Fig. 3 Engine Oil Dipstick Location—Typical

ACCEPTABLE LEVEL

To ensure proper lubrication of an engine, the en­gine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and FULL marks on the engine oil dipstick (Figs. 4
and 5). The engine oil level should be determined at
the end of each regular driving interval. The vehicle
should be on a level surface. Wait for approximately
five minutes after stopping the engine. Add engine
oil only when the level indicated on the dipstick is at
or below the ADD mark.

CAUTION: Do not overfill the engine crankcase with
oil. This will cause oil aeration and result in a de­crease in the engine oil pressure.

ADDITIVES

It is not necessary to add a special additive to en­gine oil for most types of vehicle operation. However,
the addition of special additives containing anti-rust

Fig. 5 Engine Oil Dipstick—4.0L Engine

and anti-scuff compounds can be helpful in some in­stances. For example:

• with infrequent vehicle operation or short-trip only
operation, or

• during engine break-in after a major engine over­haul and/or replacement piston installation.

MOPAR Engine Oil Supplement (or an equivalent

product) is acceptable for the conditions listed above.

ENGINE OIL FILTER

FILTER SPECIFICATION

All Jeept engines are equipped with a high quality
full-flow, throw-away type oil filter. The same type of
replacement oil filter is recommended when a re­placement is required.

J LUBRICATION AND MAINTENANCE 0 - 15

ENGINE OIL CHANGE AND FILTER REPLACEMENT

WARNING: CARE SHOULD BE TAKEN WHEN
CHANGING OIL. PROTECTIVE CLOTHING AND
GLOVES SHOULD BE WORN. EXPOSED SKIN
SHOULD BE WASHED WITH SOAP AND WATER TO
REMOVE ANY ENGINE OIL. DO NOT USE GASO­LINE, THINNER, OR SOLVENTS TO REMOVE EN­GINE OIL FROM SKIN.

REQUIRED MAINTENANCE

With normal driving conditions, engine oil and fil­ter must be changed after each 12 000-km (7,500­miles)/12-month interval. If the vehicle is involved
with a severe driving condition, after each 4 800-km
(3,000-miles)/3-month interval. A severe driving con­dition includes:

• frequent short trip driving less than 24 km (15
miles);

• frequent driving in a dusty environment;

• trailer towing;

• extensive engine idling;

• sustained high-speed operation;

• desert operation;

• frequent starting and stopping;

• cold-climate operation;

• off-road driving; or

• commercial service.

OIL CHANGE AND FILTER REPLACEMENT

(1) Drain the engine oil from the crankcase. Wait
until after the engine has attained the normal oper­ating temperature to ensure complete drainage of oil.

(2) Install the drain-hole plug with a replacement
gasket.

The oil filter should be replaced during every
engine oil change.

Rotate the oil filter counterclockwise to remove

(3)
it from the cylinder block oil filter boss (Figs. 6 and 7).

(4) Clean the cylinder block oil filter boss.
(5) Apply a light coat of engine oil to the rubber

seal on the replacement oil filter.

CAUTION: Do not use oil filter with metric threads.
The proper oil filter has SAE type 3/4 X 16 threads.
The use of an oil filter with metric threads can re­sult in engine oil leaks and engine failure.

(6) Install and hand tighten the oil filter 1/2 to
3/4 of-a-turn clockwise beyond the point where the
seal first contacts the cylinder block.

(7) Add engine oil in fill hole located on top of en­gine cylinder head cover (Fig. 8).

(8) Observe the oil level on the dipstick. Add oil,
if necessary, to increase the level to the FULL mark.

Fig. 7 Oil Filter—4.0L Engine

Fig. 6 Oil Filter Removal—2.5L Engine

Fig. 8 Adding Engine Oil—Typical

0 - 16 LUBRICATION AND MAINTENANCE J

CAUTION: Do not overfill the engine crankcase with
oil. This will cause oil aeration and result in a de­crease in the engine oil pressure.

(9) Start the engine and observe the oil pressure
gauge or warning lamp. If the pressure does not in­crease or the warning lamp does not go out, stop the
engine and determine the cause of the problem.

USED ENGINE OIL DISPOSAL

Care should be exercised when disposing used en­gine oil after it has been drained from a vehicle en­gine. Refer to the WARNING listed above.

COOLING SYSTEM

WARNING: USE EXTREME CAUTION WHEN RE­MOVING THE RADIATOR CAP IF THE ENGINE IS
OPERATING. DO NOT PUT YOUR HANDS NEAR
THE DRIVE BELT(S), PULLEYS OR FAN BLADE. DO
NOT STAND IN A DIRECT LINE WITH THE FAN
BLADE.

RECOMMENDED MAINTENANCE

The engine coolant level should be determined at
least once a month and more often during periods of
hot weather. Add coolant as necessary.

COOLANT LEVEL

With the engine at normal operating temperature,
observe the coolant level in the coolant recovery bot-
tle. The coolant level must be at least above the ADD
mark and preferably at the FULL mark. Add coolant
to the coolant recovery bottle only, if necessary.

REQUIRED MAINTENANCE

Check coolant level, and inspect condition of cool­ing system hoses and clamps after each 12 000-km
(7,500-miles).

Initially, coolant must be drained and cooling sys­tem flushed and filled after the first 36 months of op­eration. Thereafter, after each 24-months interval of
vehicle operation.

COOLANT FREEZE PROTECTION

Jeept cooling systems contain a 50/50 mixture of
anti-freeze and distilled water coolant. This is the
recommended coolant mixture for most ambient tem­peratures. The factory-installed anti-freeze is formu­lated to prevent corrosion on all cooling system metal
surfaces.

The degree of coolant freeze protection should be
tested every 12 months. If the coolant is contami­nated or rusty in appearance, cooling system should
be drained and filled with a 50/50 mixture of fresh
coolant. For additional information, refer to Group
7—Cooling System.

ENGINE AIR CLEANER FILTER ELEMENT

RECOMMENDED MAINTENANCE

Engine performance and fuel economy can be af­fected by a restricted air cleaner filter. The filter
should be inspected on a regular basis for excessive
air restriction.

If the filter element is saturated with oil, replace
the filter element.

REQUIRED MAINTENANCE

Engine air cleaner filter must be replaced after
each 48 000-km (30,000-miles).

If a vehicle is frequently operated in dusty
areas, the air cleaner filter should be inspected
often.

FILTER ELEMENT SERVICE/REPLACEMENT

(1) Remove the air cleaner cover from the body/
housing (Fig. 9).

(2) Remove the air cleaner filter element from the
body/housing.

RECOMMENDED MAINTENANCE

The engine cooling system should be inspected for
proper operation and for component failure at least
every 12 months.

WARNING: IF THE ENGINE HAS BEEN RECENTLY
OPERATED, USE EXTREME CARE WHEN REMOV­ING THE RADIATOR CAP TO AVOID SCALDING
WITH HOT, PRESSURIZED COOLANT.

For additional information, refer to Section 7, Cool­ing System.

Fig. 9 Air Cleaner & Filter Element—2.5L and 4.0L

Engines

J LUBRICATION AND MAINTENANCE 0 - 17

CAUTION: Do not tap the filter element or immerse
the filter in liquid to remove trapped particles.

(3) Clean filter element by gently blowing the
trapped particles from the filter with compressed air.
Direct air in the opposite direction of normal intake
air flow. Keep air nozzle at least two inches away
from the filter to avoid damage to filter.

(4) If the filter has become partially saturated with
oil, replace the filter. Test the crankcase ventilating
(CCV) system for proper operation.

(5) Wash the air cleaner cover and body/housing
(Figs. 10) with cleaning solvent and wipe dry.

In addition to using unleaded gasoline with the

proper octane rating, those that contain deter-

gents, corrosion and stability additives are rec­ommended. Using gasolines that have these

additives will help improve fuel economy, reduce
emissions and maintain vehicle performance. Gener­ally, premium unleaded gasolines contain more addi­tive than regular unleaded gasolines.

Poor quality gasoline can cause problems such as
hard starting, stalling and stumble. If these problems
occur, use another brand of gasoline before consider­ing servicing the vehicle.

GASOLINE/OXYGENATE BLENDS

Some fuel suppliers blend unleaded gasoline with
materials that contain oxygen such as alcohol, MTBE
and ETBE. The type and amount of oxygenate used
in the blend is important. The following are gener­ally used in gasoline blends:

ETHANOL

Ethanol (Ethyl or Grain Alcohol) properly blended,
is used as a mixture of 10 percent ethanol and 90
percent gasoline. Gasoline with ethanol may be

used in your vehicle.

Fig. 10 Air Cleaner Body/Housing & Cover

(6) Install the air cleaner filter element and attach

the cover to the body/housing.

CRANKCASE VENTILATION SYSTEM

All Jeept 2.5L and 4.0L engines are equipped with
a crankcase ventilation (CCV) system. Refer to
Group 25—Emissions, for additional information.

FUEL USAGE STATEMENT—GAS ENGINES

Jeept vehicles are designed to meet all emission
regulations and provide excellent fuel economy using
high quality unleaded gasoline. Only use unleaded
gasolines having a minimum posted octane of 87.

If a Jeept vehicle develops occasional light spark
knock (ping) at low engine speeds, this is not harm­ful. However, continued heavy knock at high

speeds can cause damage and should be
checked immediately. Engine damage as a result of

heavy knock operation may not be covered by the
new vehicle warranty.

METHANOL

CAUTION: Do not use gasolines containing metha­nol. Use of methanol/gasoline blends may result in
starting and driveability problems. In addition, dam­age may be done to critical fuel system compo­nents.

Methanol (Methyl or Wood Alcohol) is used in a va­riety of concentrations blended with unleaded gaso­line. You may encounter fuels containing 3 percent
or more methanol along with other alcohols called co­solvents.

Problems that are the result of using methanol/gas­oline blends are not the responsibility of Chrysler
Corporation. They may not be covered by the vehicle
warranty.

MTBE/ETBE

Gasoline and MTBE (Methyl Tertiary Butyl Ether)
blends are a mixture of unleaded gasoline and up to
15 percent MTBE. Gasoline and ETBE (Ethyl Ter­tiary Butyl Ether) are blends of gasoline and up to
17 percent ETBE. Gasoline blended with MTBE or
ETBE may be used.

CLEAN AIR GASOLINE

Many gasolines are now being blended that con­tribute to cleaner air, especially in those areas of the
country where air pollution levels are high. These
new blends provide a cleaner burning fuel and some
are referred to as Reformulated Gasoline.

0 - 18 LUBRICATION AND MAINTENANCE J

In areas of the country where carbon monoxide lev­els are high, gasolines are being treated with oxy­genated materials such as MTBE, ETBE and
ethanol.

Chrysler Corporation supports these efforts toward
cleaner air and recommends the use of these gaso­lines as they become available.

IGNITION CABLES, DISTRIBUTOR CAP AND
ROTOR

REQUIRED IGNITION SYSTEM MAINTENANCE

The ignition cables, distributor cap and rotor must
be replaced after each 96 000-km (60,000-miles). Re­fer to Group 8D—Ignition Systems for additional in­formation.

IGNITION TIMING

The ignition timing for 2.5L and 4.0L engines is
not adjustable. Refer to the specifications listed on
the engine Emission Control Information Label. Re­fer to Group 25—Emission Control Systems for addi­tional information.

SPARK PLUGS

REQUIRED MAINTENANCE

The spark plugs must be replaced after each 48
000-km (30,000-miles). Refer to the Spark Plugs
chart below and to Group 8D—Ignition Systems for
additional information.

SPARK PLUGS

BATTERY

RECOMMENDED MAINTENANCE

The battery electrolyte level should be checked and
the cable clamps should be inspected for corrosion.
This should be done when the oil is changed and the
oil filter is replaced.

The battery cables should be inspected for abnor­mal clamp and battery terminal post corrosion. Ser­vice the terminals and cable clamps as necessary.

In addition, the general condition of the battery
should be determined before the start of cold and hot
weather seasons. If the battery condition is marginal
or worse, it should be replaced.

Care should be taken when disposing a bat­tery after removal from a vehicle. Lead-acid bat­teries are highly poisonous and, when
indiscriminately disposed, could create a prob­lem for the environment. Contact the applicable
local city or county government agency to deter­mine where automobile (lead-acid) batteries can
be properly disposed in the local area.

INSPECTION/SERVICE

WARNING: WEAR SAFETY GLASSES, RUBBER
GLOVES AND PROTECTIVE CLOTHING WHEN HAN­DLING/SERVICING A BATTERY. THE BATTERY
ELECTROLYTE CONTAINS SULFURIC ACID AND
WILL CAUSE HARM IF IT CONTACTS SKIN, EYES
OR CLOTHING. IT WILL ALSO DAMAGE PAINTED
(AS WELL AS UN-PAINTED) SURFACES OF A VEHI­CLE. IF SULFURIC ACID CONTACTS ANY OF
THESE, FLUSH IMMEDIATELY WITH LARGE
AMOUNTS OF WATER. IF SULFURIC ACID CON­TACTS SKIN OR EYES, GET IMMEDIATE MEDICAL
ATTENTION. DO NOT SMOKE IN THE VICINITY OF
A BATTERY. KEEP OPEN FLAMES AND SPARKS
AWAY FROM BATTERY FILLER CAPS BECAUSE
EXPLOSIVE GAS IS ALWAYS PRESENT.

(1) Disconnect the battery negative cable and then
the positive cable.

(2) Clean the battery cable clamps and terminal
posts with a wire brush and a battery terminal
cleaner.

(3) Pry the battery cell filler caps upward to re­move them and inspect each filler well (low-mainte­nance batteries only, not applicable to maintenance­free batteries). It could possibly be necessary to
loosen the battery holddown clamp to remove the
caps. Maintain the electrolyte level above the battery
plates and at the bottom of the filler well ring. Add
distilled water or low-mineral content drinking wa­ter, if necessary. In freezing weather (below 0°C/
32°F), add the water just before driving to ensure
that it mixes thoroughly with the electrolyte. This
will prevent it from freezing.

(4) Remove the battery holddown strap and clean
the battery case/battery tray.Clean with bicarbonate
of soda (baking soda) and water. Rinse and dry the
battery case/tray thoroughly after cleaning.

(5) Position the battery in the tray and install the
holddown strap. Do not over-tighten the nuts.

(6) Connect the battery positive cable and then the
negative cable to the battery.

J LUBRICATION AND MAINTENANCE 0 - 19

(7) Apply a small amount of chassis lubricant (or
an equivalent protective coating) to the cable termi­nals to minimize corrosion.

RUBBER AND PLASTIC DUCTS/HOSES/TUBING

RECOMMENDED MAINTENANCE

Rubber and plastic ducts/hoses/tubing should be in­spected at the same time the engine oil is changed
and the oil filter is replaced.

The conditions associated with vehicle operation
determines the usable life of the rubber and plastic
ducts/hoses/tubing. These conditions include:

• the extent and quality of vehicle maintenance,

• the geographic area of vehicle operation, and

• the length of exposure time to excess heat and

chemical contaminants.

DUCT/HOSE/TUBING INSPECTION—EXCEPT
EMISSION CONTROL HOSES/TUBING

Refer to Group 25—Emission Control Systems.

Engine performance could be affected by air leaks
into various hoses.

Fig. 12 Intake Air Duct (XJ)—Typical

Fig. 11 Brake Booster Vacuum Hose (XJ)—Typical

Rubber/plastic ducts, hoses and tubing should
be replaced immediately if there is any evidence
of deterioration.

(1) Inspect all hose fittings for looseness and corro­sion. Inspect rubber ducts (Fig. 12) and hoses for
brittleness and cracks. Examine the hose ends (those
that are slipped over nipple connectors) for splits.

(2) Inspect surface of hoses and tubing (Fig. 13) for
heat and mechanical damage. The hose and tubing

that is located near an exhaust manifold should
be given special attention.

(3) Inspect the rubber hose routing to ensure that
the hoses do not contact any heat source, moving
component, etc., that could potentially cause heat or
mechanical damage (Figs. 14, 15, and 16).

(4) Inspect all the hose connections to ensure that
they are secure and that there is no fluid leakage. In

Fig. 13 Washer Fluid Tubing—Typical

Fig. 14 ATF Cooler Hoses —XJ Vehicles

many instances, liquid lubricants are used to aid in
the connection of hoses to couplings.

0 - 20 LUBRICATION AND MAINTENANCE J

ACCESSORY DRIVE BELT

RECOMMENDED MAINTENANCE

The accessory drive belt should be inspected for
cracks, fraying, and excessive wear. If necessary, re­fer to Group 7—Cooling Systems for replacement pro­cedures and adjustment specifications.

REQUIRED MAINTENANCE

The drive belt must be adjusted after each 48
000-km (30,000-miles) interval of vehicle operation
has elapsed. The accessory drive belt must be re­placed after each 96 000-km (60,000-miles). If neces­sary, refer to Group 7—Cooling Systems.

EXHAUST SYSTEM

Fig. 15 ATF Cooler Hoses —XJ Vehicles

REQUIRED MAINTENANCE

The general condition of the exhaust system must
be inspected after each 12 000-km (7,500-miles).

An exhaust system must be properly aligned to
prevent stress, leakage, and vehicle body contact.

Fig. 16 ATF Cooler Hoses (4.0L)—YJ Vehicles

ENGINE SUPPORTS

RECOMMENDED MAINTENANCE

The general condition of the engine supports
should be inspected at the same time as the engine
oil is changed and the oil filter is replaced.

INSPECTION

(1) Test the hardware that attaches the engine cyl­inder block to the engine support brackets (Figs. 17
and 18) for the specified tightening torque.

(2) Inspect the rubber in the engine support cush­ions for softening and swelling. Slight surface deteri­oration and wear at the ends will not affect the
functioning of an engine support.

Fig. 17 Front Engine Support—Typical

Fig. 18 Rear Engine Support—Typical

J LUBRICATION AND MAINTENANCE 0 - 21

INSPECTION

When inspecting an exhaust system, inspect for
cracked or loose joints, stripped screw/bolt threads,
corrosion damage, and worn or broken hangers. Re­place all components that are corroded or damaged.
Do not attempt repair. Also, inspect for the following
obvious conditions and correct as necessary:

• exhaust system leaks, damage, misalignment;

• contact with body panels metal or the frame; and

• catalytic converter bulging or excessive heat dam-

age.

CAUTION: A catalytic converter will become con­taminated if leaded gasoline is burned in the en­gine. If this occurs, the complete converter must be
replaced.

AIR-CONDITIONER COMPRESSOR/HOSES/
FITTINGS

RECOMMENDED MAINTENANCE

The general condition of the A/C compressor, hoses
and fittings should be inspected at the same time as
the engine oil is changed (Figs. 19, 20 and 21).

LUBRICANT AND REFRIGERANT

In addition to inspection, the lubricant level in the
compressor (Fig. 22) should be determined if there
are indications that oil was lost.

Loss of lubricating oil usually accompanies a loss of
refrigerant. The presence of bubbles/white foam
within the receiver/drier sight glass indicates that
some loss of refrigerant has occurred.

For additional information involving the A/C sys­tem, refer to Group 24—Heater And Air Conditioning.

Fig. 19 A/C System (XJ)—2.5L Engine

Fig. 20 A/C System (XJ)—4.0L Engine

Fig. 21 A/C System (YJ)—4.0L Engine

Fig. 22 A/C Compressor—Typical

0 - 22 LUBRICATION AND MAINTENANCE J

DRIVETRAIN

INDEX

page page

Automatic Transmission .................... 23

Drive Shafts ............................ 27

Front and Rear Axles ..................... 26

Hydraulic Clutch ......................... 22

HYDRAULIC CLUTCH

RECOMMENDED MAINTENANCE

Check fluid level in the hydraulic clutch master
cylinder reservoir (Fig. 1) at the same time engine
oil is changed and oil filter is replaced. Add fluid as
necessary.

Manual Transmission ...................... 22

Rubber and Plastic Hoses/Tubing ............ 28

Transfer Case ........................... 25

relation to the level indicator ring (Fig. 3) located in­side the reservoir. If necessary, add fluid until the
height is level with the indicator ring.

Fig. 2 Hydraulic Clutch Master Cylinder Fluid

Reservoir

Fig. 1 Hydraulic Clutch (YJ)—Typical

FLUID SPECIFICATION

The only fluid recommended for use in a hydraulic
clutch system is MOPAR Brake And Hydraulic
Clutch Fluid., or an equivalent fluid.

CAUTION: Never use reclaimed brake fluid or fluid
from an unsealed container. In addition, do not use
fluid from a container that has been opened and al­lowed to stand for an extended length of time.
Moisture in the air can be absorbed by the fluid,
which causes dilution with loss of effectiveness.

FLUID LEVEL

Remove the master cylinder fluid reservoir cap
(Fig. 2). The fluid level is determined by its height in

Fig. 3 Hydraulic Clutch Fluid Level

MANUAL TRANSMISSION

RECOMMENDED MAINTENANCE

The lube oil level in manual transmissions should
be determined at the same time as the engine oil is
changed and the oil filter is replaced. Add lube oil as
necessary.

J LUBRICATION AND MAINTENANCE 0 - 23

Under normal driving conditions, manual trans­mission lube oil should be changed after each 60
000-km (37,500 miles). With severe driving condi­tions, after each 29 000-km (18,000 miles).

LUBRICANT SPECIFICATION

When it becomes necessary to add to or change the
lube oil in a Jeept manual transmission, use SAE
75W-90, API Quality Grade GL-5 gear lubricant.

LUBRICANT LEVEL

The fill-hole plug for all manual transmissions is
located on the right side of the case (Fig. 4). Deter­mine the lubricant level according to the following
procedure.

(4) Remove the drain-hole plug and drain the lube

oil from the transmission into the container.

Care should be exercised when disposing used
lube oil after it has been drained from a trans­mission.

(5) Install the drain-hole plug in the transmission.
Tighten the plug with 37 NIm (27 ft. lbs.) torque.

(6) Fill the transmission until the lube oil begins
to drip out of the fill hole with SAE 75W-90, API
Quality Grade GL-5 gear lubricant.

(7) Install the fill-hole plug in the transmission.
Tighten the plug with 37 NIm (27 ft. lbs.) torque.

(8) Remove the support and lower the vehicle.

AUTOMATIC TRANSMISSION

RECOMMENDED MAINTENANCE

Check fluid level in automatic transmissions (Fig.

5) the same time the engine oil is changed and the
oil filter is replaced. Add ATF as necessary.

Fig. 4 Manual Transmission Fill- & Drain-Hole

Plugs—Typical

(1) Remove the fill-hole plug (Fig. 4) from the
transmission. The lube oil should be level with the
bottom edge of the fill hole. The level can be slightly
below the bottom edge of the fill hole if the lube oil
is cold.

If the transmission is warm, lube oil could drip
out of the fill hole. This is acceptable but the
lube oil should not gush out of the fill hole.

(2) If not acceptable, raise the lube oil level to the
bottom edge of the transmission fill hole. Use SAE
75W-90, API Quality Grade GL-5 gear lubricant.

Add lube oil in small amounts to raise the
level.

(3) Install the fill-hole plug in the transmission.
Tighten the plug with 37 NIm (27 ft. lbs.) torque.

LUBE OIL CHANGE

When it becomes necessary to change manual
transmission lube oil, use the following procedure.

(1) Raise and support the vehicle.

(2) Remove the fill-hole plug from the transmis­sion.

(3) Place a container to collect the lube oil under
the transmission drain-hole plug.

Fig. 5 AW-4 Automatic Transmission (XJ)

Under normal driving conditions, the ATF should
be changed and the filter replaced after each 48
000-km (30,000-miles). With severe driving condi­tions, after each 29 000-km (12,000-miles).

ATF SPECIFICATIONS

When it becomes necessary to add fluid (ATF) to a
Jeept automatic transmission (or when the ATF is
replaced), use:

• Mercon™ ATF only for AW-4 automatic transmis-
sions (XJ vehicles), and

• MOPAR ATF PLUS type 7176 (or an equivalent
Mercon™/Dexron II™ ATF) for 998 automatic trans­missions (YJ vehicles).

SPECIAL ADDITIVES

The addition of any special-type fluid to a Jeept
automatic transmission is not recommended. The
only exception is the addition of black-light detection

0 - 24 LUBRICATION AND MAINTENANCE J

dye to aid in detecting the source of ATF leaks. The
use of transmission sealing additives should also be
avoided.

Black-light detection dye is factory-installed in
automatic transmissions and, unless the ATF
has been drained and re-placed, it is not neces­sary to add dye.

ATF LEVEL

Determine the ATF level according to the following
procedure.

WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT PUT YOUR
HANDS NEAR THE DRIVE BELT, PULLEYS OR FAN
BLADE. DO NOT STAND IN A DIRECT LINE WITH
THE FAN BLADE.

(1) Operate the engine and allow the automatic
transmission sufficient time to warm to the normal
operating temperature (77°C/170°F).

When at normal operating temperature, ATF
will be uncomfortable to fingertips when the
dipstick is touched. Normally, 25 km (15 miles) is
a sufficient driving distance for a transmission
to warm to normal operating temperature (77°C/
170°F).

(2) Place the vehicle on a level surface.

(3) Operate the engine at idle speed.

(4) Engage the parking brake.

(5) Place a block in front of and at the rear of one
wheel/tire to prevent vehicle movement.

(6) Depress the brake pedal and move the trans­mission selector lever through all the positions and
then place the selector lever in NEUTRAL position.

(7) Remove the dipstick (Fig. 6) from the transmis­sion filler tube and wipe it clean.

(8) Insert the dipstick into the transmission filler
tube and seat the cap on top of the tube.

(9) Remove the dipstick and observe the ATF level
on both sides of the dipstick. The ATF level is accept­able when it is between the ADD and FULL marks.

(10) While determining the ATF level in a trans­mission, also note the general condition of the fluid.
Examine the fluid closely. If doubtful about its con­dition, drain a sample into a small container for
evaluation.

(11) If the ATF level is either at or below the ADD
mark, add sufficient ATF to raise the level to the
FULL mark on the dipstick.

CAUTION: Do not over-fill an automatic transmis­sion. Over-filling can cause the ATF to foam, which
will result in over-heating, fluid oxidation and var­nish formation.

(12) When it is necessary to add ATF, insert a
long-necked funnel into the transmission filler tube.

It requires only 0.5 liter (1.0 pint) of ATF to raise
the level from the ADD mark to the FULL mark.

sary.

ATF AND FILTER CHANGE

riorate or wear out, but it does become contaminated.
These contaminates will eventually restrict passages
and orifices. The result is hard or rough shifting, or
complete transmission failure. Also, the varnish
eventually causes rubber seals to harden and become
brittle.

place the filter in a Jeept automatic transmission,
use the following procedures.

Fig. 6 Dipstick & ATF Level—Typical

Fig. 7 Safe ATF Level Above 22°C/72°F

(13) Inspect for ATF leaks and correct as neces­(14) Remove the wheel/tire blocks.

Automatic transmission fluid (ATF) does not dete-

When it is necessary to change the ATF and re-

J LUBRICATION AND MAINTENANCE 0 - 25

DRAINING ATF/FILTER REMOVAL

Drain the automatic transmission fluid (ATF) im­mediately after stopping the engine (before the ATF
cools).

(1) Raise and support the vehicle.

(2) Loosen the transmission pan bolts and drain
the original ATF into an appropriate container. Re­move the pan bolts, the pan and the gasket.

Care should be exercised when disposing used
ATF after it has been drained from a vehicle
transmission.

(3) Remove the screws and the ATF filter (Fig. 8).
Discard the filter.

(8) With the transmission at normal operating
temperature, observe the ATF level on the dipstick.
Add ATF (if necessary) to raise the level to the
FULL mark on the dipstick. Only 0.5 liter (1.0 pint)

will raise the level from the ADD mark to the
FULL mark when the ATF is at normal operat­ing temperature.

(9) Inspect for fluid leaks and correct as necessary.

(10) Remove the wheel/tire blocks.

TRANSFER CASE

RECOMMENDED MAINTENANCE

The fluid (ATF) level in transfer cases should be
determined at the same time as the engine oil is
changed and the oil filter is replaced. Add ATF as
necessary.

In addition, transfer case ATF should be changed
after each 48 000-km (30,000-miles) interval of vehi­cle operation has elapsed.

FLUID SPECIFICATIONS

If it is necessary to add fluid to a transfer case (or
when the fluid is changed), use MOPAR ATF PLUS
type 7176 or an equivalent Mercon™/Dexron II™
ATF.

Fig. 8 ATF Filter—Typical

FILTER INSTALLATION/ATF RE-FILL

(1) Install a replacement ATF filter. Tighten the

screws with 4 NIm (35 in. lbs.) torque.

(2) Clean the pan thoroughly. Install a replace­ment gasket on the pan. Install the pan with the at­taching bolts:

• model AW-4 transmission — tighten the pan bolts
with 7 NIm (60 in. lbs.) torque; and

• model 998 transmission — tighten the pan bolts
with 17 NIm (150 in. lbs.) torque.

(3) Remove the support and lower the vehicle.

(4) Pour approximately 4.7 liters (5 quarts) of ATF
into the filler tube. Use Mercon™ ATF for AW-4 au­tomatic transmissions. Use MOPAR ATF PLUS type
7176 or equivalent, for 998 automatic transmissions.

(5) Place a block in front of and at the rear of one
wheel/tire to prevent vehicle movement.

(6) Start the engine and allow it to idle a few min­utes.

(7) Apply the brake pedal and engage the parking
brake. Move the transmission selector lever through
all positions, then place the selector lever in NEU­TRAL position.

FLUID LEVEL

The transfer case fill-hole plug is located at the

rear of the housing (Fig. 9).

Fig. 9 Transfer Case—Typical

Determine the transfer case fluid (ATF) level ac-

cording to the following procedure.

(1) Raise and support the vehicle.

(2) Remove the fill-hole plug from the transfer
case. The ATF level should be at the bottom edge of
the fill hole. The level can be slightly below the bot­tom edge of the fill hole if the fluid is cold.

0 - 26 LUBRICATION AND MAINTENANCE J

If the transfer case ATF is warm, it is accept­able for the fluid to drip out of the fill hole. If
the fluid gushes out of the fill hole, the level is
too high.

(3) If the level is low, raise it to the bottom edge of
the fill hole with MOPAR ATF PLUS type 7176 or
an equivalent Mercon™/Dexron II™ ATF.

(4) Install the fill-hole plug. Tighten the plug with
47 NIm (35 ft. lbs.) torque.

(5) Remove the support and lower the vehicle.

FLUID CHANGE

When it becomes necessary to change the ATF in a
Jeept transfer case, use the following procedure.

(1) Raise and support the vehicle.

(2) Remove the fill-hole plug from the transfer
case.

(3) Place an appropriate container under the trans­fer case drain-hole plug.

(4) Remove the drain-hole plug and drain the ATF
from the transfer case into the container.

Care should be exercised when disposing used
ATF after it has been drained from a transfer
case.

lubricant in the rear axle. XJ Vehicles equipped
with a class III trailer hitch require SAE
75W-140 synthetic gear lubricant in the rear
axle.

LUBRICANT LEVEL

Determine the axle differential housing lubricant

level according to the following procedure.

(1) Raise and support the vehicle.

(2) Remove the fill-hole plug (Figs. 10 and 11)
from the axle differential housing cover. The gear lu­bricant should be 13 mm (1/2 inch) below the bottom
edge of the fill hole.

CAUTION: Do not over-tighten the drain and fill-hole
plugs. Over-tightening can strip the hole threads
and/or crack the aluminum housing.

(5) Install the drain-hole plug in the transfer case.

Tighten the plug with 47 NIm (35 ft. lbs.) torque.

(6) Fill the transfer case to the bottom edge of the
fill hole with MOPAR ATF PLUS type 7176 (or an
equivalent Mercon™/Dexron II™ ATF).

(7) Install the fill-hole plug in the transfer case.
Tighten the plug with 47 NIm (35 ft. lbs.) torque.

(8) Remove the support and lower the vehicle.

FRONT AND REAR AXLES

RECOMMENDED MAINTENANCE

The lubricant level in axle differential housings
should be determined at the same time as the engine
oil is changed and the oil filter is replaced. Add lu­bricant as necessary.

In addition, with normal driving conditions, the
axle lubricant should be changed after each 48
000-km (30,000-miles). With severe driving condi­tions, after each 29 000-km (12,000-miles).

LUBRICANT SPECIFICATIONS

For normal vehicle operation, use SAE 75W-90,
API Quality Grade GL-5 gear lubricant in all Jeept
front (4WD only) and rear axles. Vehicles equipped
with a Trac-Loc rear axle also require a friction mod­ifier additive with the gear lubricant.

When involved in trailer towing applications
use SAE 80W-140, API Quality Grade GL-5 gear

Fig. 10 Rear Axle—Typical

Fig. 11 Front Axle (4WD)—Typical

(3) If not acceptable, raise the lubricant level to 13

mm (1/2 inch) below the bottom edge of the fill hole.

Add lubricant in small amounts to raise the

level.

(4) Install the fill-hole plug in the differential
housing cover. Tighten the plug with 34 N°m (25 ft.
lbs.) torque.

(5) Remove the support and lower the vehicle.

J LUBRICATION AND MAINTENANCE 0 - 27

LUBRICANT CHANGE

When it becomes necessary to change the axle lu­bricant in a Jeept front or rear axle, use the follow­ing procedure.

(1) Raise and support the vehicle.

(2) Place a container under the axle differential
housing.

(3) Remove the axle differential housing cover
bolts. Remove the housing cover.

(4) Allow the axle gear lubricant to completely
drain into the container.

CAUTION: Do not flush a rear axle Trac-Loc differ­ential. Trac-Loc differentials may be cleaned only
by disassembling the unit and wiping the compo­nents with clean, lint-free cloth.

Fig. 13 Differential Housing Cover Installed

(5) Flush the inside of the differential housing
with a flushing oil. Do not use water, steam, ker-

osene or gasoline for flushing.

(6) Remove any residual RTV sealant/gasket mate­rial from the differential housing and cover. Thor­oughly clean the contact surfaces with mineral
spirits and dry the surfaces completely.

(7) Apply a‘bead of MOPAR RTV Sealant, or an
equivalent sealant, around the bolt circle on the
housing and on the cover (Fig. 12).

(9) Remove the fill-hole plug and add the replace­ment gear lubricant to the differential housing. Refer
to Specifications above.

(10) Install the fill-hole plug. Tighten the plug
with 34 N°m (25 ft. lbs.) torque.

(11) Remove the support and lower the vehicle.

DRIVE SHAFTS

RECOMMENDED LUBRICATION

With normal driving conditions, the drive shaft
U-joint couplers and slip yoke splines (Figs. 14 and

15) should be lubricated after each 12 000-km (7,500­miles). With severe driving conditions, after each 4
800-km (3,000-miles).

Fig. 12 RTV Sealant Application—Typical

If differential housing cover is not installed
within 20 minutes after applying sealant, the
sealant must be removed and another bead ap­plied.

(8) Install the cover on the differential housing
with the attaching bolts (Fig. 13). Tighten the cover
bolts with 47 NIm (35 ft. lbs.) torque.

Fig. 14 Front Drive Shaft (4WD)—Typical

0 - 28 LUBRICATION AND MAINTENANCE J

• the extent and quality of vehicle maintenance,

• the geographic area of vehicle operation, and

• the length of exposure time to excess heat and

chemical contaminants.

(1) Inspect all hose and tubing fittings for loose­ness and corrosion. Inspect the rubber hoses for brit­tleness and cracks. Thoroughly inspect the hose ends
(those that are slipped over nipple connectors) for
splits (Figs. 16, 17, 18, 19, 20, 21 and 22).

Fig. 15 Rear Drive Shaft (4WD)—Typical

CAUTION: It is very important that drive shafts be
lubricated at periodic intervals and that the speci­fied type of lubricant be used. Failure to properly
lubricate could result in premature wear of drive
shaft components.

LUBRICATION FITTINGS

The drive shaft universal-joint couplers (U-joints)
and the front drive shaft slip yoke splines are
equipped with Zerk fittings. The (CV-joints) are lu­bricated when assembled during manufacture and do
not require additional lubrication.

LUBRICANT SPECIFICATION

Drive shaft U-joint couplers and slip yoke splines
should be lubricated with a lubricant that is identi­fied as NLGI GC-LB lubricant.

SLIP-YOKE SPLINE LUBRICATION

The method below will ensure complete lubrication
of the front drive shaft slip-yoke splines (Fig. 14).

(1) Clean the tips of the Zerk type fittings.

(2) Use a gun or another appropriate lubricant dis­penser to force pressurized lubricant into the slip
yoke Zerk fittings.

(3) When the lubricant appears, cover the pressure
relief hole with a finger. Force pressurized lubricant
into fitting until it appears at slip-yoke seal.

RUBBER AND PLASTIC HOSES/TUBING

Fig. 16 Front Axle Vent Hose (4WD)—XJ Vehicles

RECOMMENDED MAINTENANCE

The condition of underbody rubber hose and plastic
tubing should be inspected for failure at the same
time as oil is changed and oil filter is replaced.

HOSE/TUBING INSPECTION

Vehicle operating conditions determine the useable
life of underbody hoses and tubing. These conditions
include:

Fig. 17 Front Axle Vent Hose—YJ Vehicles

J LUBRICATION AND MAINTENANCE 0 - 29

Fig. 18 Front Axle Vacuum Shift Tubing

Fig. 19 Transfer Case Vent Hose (4WD)—Typical

Fig. 21 Rear Axle Vent Hose—YJ Vehicles

Fig. 22 Rear Axle Vent Hose At Wheelhouse—YJ

Vehicles

(2) Inspect the surface of hoses and tubing for heat
and mechanical damage. Hose and tubing located
close to an exhaust pipe should be given special at­tention.

(3) Inspect the rubber hose routing to ensure that
the hoses do not contact any heat source, moving
component, etc., that would potentially cause heat or
mechanical damage.

(4) Inspect all the hose connections to ensure that
they are secure and there is no fluid leakage. Actual
dripping of hot fluid should be noted and the clamps
tightened in an attempt to stop the leakage before
replacing the hose.

Fig. 20 Rear Axle Vent Hose—XJ Vehicles

0 - 30 LUBRICATION AND MAINTENANCE J

CHASSIS AND BODY COMPONENTS

INDEX

page page

Body Components ........................ 34

Chassis Component and Wheel Bearing

Lubricants ............................ 30

Front Wheel Bearings ..................... 31

Headlamps .............................35

CHASSIS COMPONENT AND WHEEL BEARING
LUBRICANTS

The chassis component and wheel bearing lubri­cants that are recommended for Jeept vehicles are
identified by the NLGI Certification Symbol (Fig. 1).
The symbol contains a coded designation that identi­fies the usage and quality of the lubricant.

Manual Steering Gear—YJ Vehicles .......... 32

Power Brake System ...................... 32

Power Steering System .................... 31

Steering Linkage and Ball Studs ............. 30

Tires ..................................34

Fig. 2 Steering Components (XJ)—Typical

LUBRICANT SPECIFICATION

Steering linkage should be lubricated with a dual­purpose, lithium-base lubricant that is identified as
NLGI GC-LB lubricant.

Fig. 1 NLGI Lubricant Container Certification/

Identification Symbol

The letter G designates wheel bearing lubricant.
Letter L designates chassis lubricant. When the let­ters are combined the lubricant can be used for dual
applications. The suffix letters C and B designate the
level of the lubricant for the application. The letter C
represents level available for wheel bearing lubricant
(G) and the letter B represents level available for
chassis lubricant (L).

STEERING LINKAGE AND BALL STUDS

RECOMMENDED MAINTENANCE

The general condition of the steering linkage (Fig.

2) should be inspected and the ball studs should be
lubricated:

• 2WD vehicles — after each 24 000-km (15,000­miles) or six-months interval of vehicle operation has
elapsed; or

• 4WD vehicles — after each 12 000-km (7,500­miles) or six-months interval of vehicle operation has
elapsed.

INSPECTION/LUBRICATION

(1) Inspect the steering linkage. Examine the tie
rods and the drag link for bending, and the ball
studs for looseness and excessive wear.

(2) Replace, as necessary, all torn/ruptured ball­stud seals and damaged/defective steering linkage
components.

CAUTION: Use care to prevent lubricant from con­tacting the brake rotors.

(3) Lubricate the ball studs:

• clean the tips of the Zerk type lubrication fittings
on the tie-rod and drag-link ball-stud ends to avoid
lubricant contamination;

• lubricate the ball studs with high quality, dual­purpose, lithium base chassis/wheel bearing lubri­cant (NLGI GC-LB lubricant);

• cease the lubricant pressure when lubricant begins
to freely exit the base of the seal, or if the seal be­gins to expand; and

• wipe the excess lubricant from the exterior sur­faces of the ball joints and the adjacent surfaces.

J LUBRICATION AND MAINTENANCE 0 - 31

FRONT WHEEL BEARINGS

Only 2WD XJ vehicles are equipped with front
wheel bearings. XJ vehicles have semi-floating axle
shafts and axle shaft bearings that are lubricated via
differential lube oil.

RECOMMENDED MAINTENANCE—2WD XJ
VEHICLES

The front wheel bearings should be lubricated (re­packed) at the same time as front brake pad/caliper
service is conducted.

LUBRICANT SPECIFICATION

Wheel bearings should be lubricated with a lubri­cant that is identified as NLGI GC-LB lubricant.

INSPECTION/LUBRICATION

(1) Remove the wheel/tire and the disc brake cali­per. Do not disconnect the caliper brake fluid

hose unless the caliper must also be removed for
maintenance. Support the caliper with a hanger
to prevent brake fluid hose damage.

(2) Remove the dust cap, the cotter pin, the nut re­tainer, the adjustment nut, and the thrust washer
from the spindle (Fig. 3). Discard the cotter pin.

ing and bearing damage. Also, excessive lubricant
can be forced out of the wheel hub cavity and con­taminate the brake rotor/pads.

(8) Partially fill the wheel hub cavity with chassis/

wheel bearing lubricant (NLGI GC-LB lubricant).

(9) Pack the wheel bearings with chassis/wheel
bearing lubricant (NLGI GC-LB lubricant). Ensure
that sufficient lubricant is forced between the bear­ing rollers.

(10) Install the wheel inner bearing in the wheel
hub and install a replacement seal.

(11) Clean the disc brake rotor contact surfaces, if
necessary.

(12) Install the wheel hub/disc brake rotor on the
spindle.

(13) Install the wheel outer bearing, the thrust
washer, and the spindle nut.

(14) Tighten the spindle nut with 28 NIm (21 ft.
lbs.) torque while rotating the disc brake rotor to
seat the bearings.

(15) Loosen the spindle nut 1/2 turn. While rotat­ing the disc brake rotor, tighten the spindle nut with
2NIm (19 in. lbs.) torque.

(16) Install the nut retainer and a replacement cot­ter pin.

(17) Clean the dust cap and apply wheel bearing
lubricant to the inside surface. Do not fill the dust

cap with lubricant.

(18) Install the dust cap.

(19) Install the disc brake caliper.

Fig. 3 2WD Front Wheel Bearings—XJ Vehicles

(3) Remove the wheel outer bearing from the hub.
(4) Remove the wheel hub/disc brake rotor from

the spindle.

(5) Remove the seal and the inner wheel bearing

from the hub cavity.

(6) After removal, inspect both front wheel bearing
races for indications of pitting, brinelling and exces­sive heat.

(7) Wipe the spindle clean and apply a small
amount of chassis/wheel bearing lubricant (NLGI
GC-LB lubricant) to prevent rust. Wipe the wheel
hub cavity clean.

CAUTION: Do not over-fill the wheel hub cavity with
lubricant. Excessive lubricant can cause overheat-

POWER STEERING SYSTEM

RECOMMENDED MAINTENANCE

The condition of power steering system should be
inspected and the fluid level checked. Add fluid as
necessary.

FLUID SPECIFICATION

Jeept power steering systems require MOPAR
Power Steering Fluid, or an equivalent product.

The original power steering fluid installed in
Jeept vehicles includes black-light leak detec­tion dye.

INSPECTION

Inspect the power steering system (Figs. 4 and 5)
for the sources of fluid leaks, steering gear housing
cracks and ensure that the steering gear is securely
attached to the vehicle frame rail. Inspect the steer­ing damper for leaks and loose connections.

FLUID LEVEL

The fluid level dipstick is attached to the reservoir
cap (Fig. 6). The fluid level in the reservoir can be
determined with the fluid either hot or cold.

(1) Remove the cap from the reservoir.

0 - 32 LUBRICATION AND MAINTENANCE J

Fig. 6 Power Steering Fluid Reservoir

Dipstick—Typical

Fig. 4 Power Steering System—XJ Vehicles

essary (refer to Group 19—Steering for additional in­formation and service procedures).

Fig. 5 Power Steering System—YJ Vehicles

(2) Depending on fluid temperature, if the level is
below the FULL HOT mark or the FULL COLD
mark on the dipstick, add power steering fluid.

(3) Install the cap on the reservoir.

MANUAL STEERING GEAR—YJ VEHICLES

RECOMMENDED MAINTENANCE

The manual steering gear should be inspected for
damage at the same time as the engine oil is
changed and the oil filter is replaced. Repair as nec-

POWER BRAKE SYSTEM

RECOMMENDED MAINTENANCE

The condition of the brake system should be in­spected and the fluid level in the master cylinder
should be checked each time the brake system is ser­viced. Add brake fluid and repair as necessary.

In addition, the brake system should be operation­ally tested periodically to ensure that it is function­ing normally.

FLUID SPECIFICATION

Jeept power brake systems require MOPAR
Heavy-Duty Brake Fluid, or an equivalent product
identified as conforming to FMVSS No. 116, DOT-3
and SAE J-1703 specifications.

Use new brake fluid only when adding fluid to
the reservoir, to fill the brake system. Never use re­claimed fluid.

BRAKE FLUID LEVEL

STANDARD POWER BRAKE SYSTEM

(1) Clean the cover and the sides of the brake fluid
reservoir.

(2) Detach the bail retainer from the reservoir
cover and remove the cover from the reservoir.

(3) The brake fluid level should be 6 mm (1/4 in)
below the rim of each reservoir well for XJ and YJ
Vehicles (Fig. 7). If not, add brake fluid as necessary.

(4) Inspect the reservoir cover bail retainer for ten­sion and the cover for proper fit. The cover should fit
tight and have a good seal.

J LUBRICATION AND MAINTENANCE 0 - 33

Fig. 7 Reservoir Fluid Level—Typical

(5) Inspect the reservoir rubber diaphragm seal for

cracks, cuts and distortion.

(6) Inspect the brake fluid tubing fittings and the
master cylinder housing for indications of fluid leak­age. Repair as necessary.

(7) Install the brake fluid reservoir cover.

ANTI-LOCK BRAKE SYSTEM—XJ VEHICLES

The anti-lock brake system fluid reservoir for XJ
Vehicles is located in the engine compartment at the
left side of the dash panel.

(1) Turn the ignition switch ON and allow the
pump motor to operate until it automatically de-en­ergizes.

(2) Clean the cover before removing it.

CAUTION: Over-filling could cause fluid overflow
and possible reservoir damage when the pump mo­tor energizes.

(3) The brake fluid level should be no lower than
the MIN arrow indicator on the side of the reservoir
(Fig. 8). If not, add brake fluid as necessary. Raise
the fluid level to the MAX arrow indicator only. Do
not over-fill the reservoir.

(4) Turn the ignition switch OFF.

BRAKE SYSTEM INSPECTION

BRAKE FLUID HOSES/TUBING

(1) Inspect all brake fluid rubber hoses (Fig. 9) for
cracks, swelling, kinks, a distorted condition and
fluid leakage.

(2) Inspect the brake fluid hoses and tubing that
are routed along the frame rail.

PADS/LININGS, ADJUSTER, WHEEL CYLINDERS AND
CALIPER

The front disk brake pads can be visually inspected
via the brake caliper inspection ports.

Fig. 8 Reservoir Fluid Level—Anti-Lock Brake

System

Fig. 9 Rubber Brake Fluid Hose—Typical

(1) Inspect the brake pads and linings for excessive

wear, cracks, charred surfaces and broken rivets.

(2) Inspect the brake pads and linings for contam­ination with brake fluid, axle lubricant and/or an­other fluid.

(3) Replace the brake pads and/or linings if they
are worn to within 0.78 mm (1/32 in) of the rivet
head.

(4) Operate the rear brake self-adjuster lever and
pivot. Test the operation of the self-adjuster screw for
ease of movement.

(5) Inspect the self-adjuster components for bent
areas, frayed cables, loose or overheated springs, and
a binding condition.

0 - 34 LUBRICATION AND MAINTENANCE J

(6) Inspect the disc brake caliper dust boot for cor­rect installation, damage/tears and indications of
brake fluid leakage. Inspect the bushings and pins
for corrosion, tears and a binding condition.

(7) Pull the rear wheel cylinder dust boot back to
expose the wheel cylinder housing and inspect for
fluid leaks. Inspect the pistons and cylinder bores for
proper appearance.

(8) Inspect the brake differential warning valve
and housing for indications of leakage, kinked hoses
and loose fittings.

PARK BRAKE

(1) As applicable, engage the park brake lever or
pedal and then release it.

(2) If the park brake is functioning normally, test
it for smooth operation and vehicle-holding capabil­ity.

(3) Inspect the park brake cables for kinks, fraying
and a binding condition.

(4) With the park brake released, the rear wheels
should rotate without restriction. Adjust the park
brake cable tension at the equalizer (Fig. 10), if nec­essary.

TIRES

RECOMMENDED MAINTENANCE

The general condition of the tires and the inflation
pressures should be inspected at the same time the
engine oil is changed and the oil filter is replaced.

In addition, the tires/wheels should be rotated pe­riodically to ensure even tread wear and maximum
tread life. The tires/wheels should be rotated initially
after the first 12 000-km (7,500-miles). Thereafter,
after each 24 000-km (15,000-miles) interval of vehi­cle operation has elapsed.

INSPECTION

Inspect the tires for excessive wear, damage, etc.
Test the tires for the recommended inflation pres­sure. Refer to the tire inflation pressure decal located
on the inside of the glove box door, and also to Group
22—Tires And Wheels.

ROTATION

Refer to Group 22—Tires And Wheels for the rec­ommended method of tire/wheel rotation for a Jeept
vehicle.

BODY COMPONENTS

Fig. 10 Park Brake Equalizer (XJ)—Typical

(5) Repair any park brake malfunctions.

BRAKE OPERATIONAL TEST

(1) Drive the vehicle and test for proper brake ac-

tion.

(2) Note any indication of drum/rotor overheating,
wheel dragging or the vehicle pulling to one side
when the brakes are applied.

(3) Evaluate any performance complaints received
from the owner/operator.

(4) Repair the brake system as necessary (refer to
Group 5—Brakes for additional information and ser­vice procedures).

RECOMMENDED MAINTENANCE

Body components should be lubricated (as required)
after each 48 000-km (30,000-miles) interval of vehi­cle operation has elapsed.

LUBRICANT SPECIFICATIONS

All applicable exterior and interior body compo­nents should be:

• inspected for excessive wear,

• cleaned, and

• all pivot/sliding contact areas of the components

should be lubricated with the specified lubricant.

Refer to the Body Lubricant Specifications chart
below. When excessive wear is apparent, replace/re­pair as necessary.

LUBRICATION

All pivoting and sliding contact areas, including:

• seat tracks,

• door hinges/latches/strikers, and

• liftgate/tailgate/hood hinges (Fig. 11),

should be lubricated periodically to ensure quiet,
easy operation and to protect against wear and cor­rosion.

(1) As required, lubricate the body components
with the specified lubricants.

(2) When lubricating door weatherstrip seals, ap­ply the lubricant to a cloth and wipe it on the seal.

(3) Prior to the application of lubricant, the compo­nent should be wiped clean to remove dust, grit and
debris. After lubrication, any excess lubricant should
be removed.

J LUBRICATION AND MAINTENANCE 0 - 35

BODY LUBRICANT SPECIFICATIONS

Fig. 11 Hood Hinge Lubrication—XJ Vehicles

(4) Extra close attention should be given to exter­nal key lock cylinders during the autumn and winter
months to ensure protection from water and ice.

(5) Extra close attention should also be given to
the hood latch components to ensure proper function­ing.

HEADLAMPS

RECOMMENDED MAINTENANCE

Approximately every six months the headlamps
should be displayed on a vertical test surface. This
will ensure that the headlamps are positioned for
safe night-time driving.

BEAM AIM ADJUSTMENT

(1) Changes in the vehicle front and rear suspen­sion will alter the headlamp beam patterns and this
can cause unsafe night-time driving conditions.

(2) If a vehicle is loaded the headlamp beam pat­terns should be displayed on an vertical test surface
and the headlamps re-aimed.

(3) Observe the headlamp beam patterns on an ap­propriate vertical test surface and, if necessary, ad­just the headlamp beam aim.

(4) If necessary, refer to Group 8L—Lamps for
headlamp aim adjustment procedures.

J FRONT SUSPENSION AND AXLE 2 - 1

FRONT SUSPENSION AND AXLE

CONTENTS

page page

AXLE NOISE/VIBRATION DIAGNOSIS ....... 16

FRONT WHEEL ALIGNMENT ............... 5

GENERAL INFORMATION .................. 1

MODEL 30 AXLE AND TUBE AXLE (2WD) .. 20

GENERAL INFORMATION

FRONT SUSPENSION

XJ VEHICLES

The Cherokee front suspension is a link/coil design

comprised of (Fig. 1);

• Drive axle (4WD), tube axle (2WD)

• Track bar

• Stabilizer bar

• Upper and lower suspension arms

• Coil springs

• Dual-action shock absorbers

TORQUE SPECIFICATIONS ................ 47

XJ FRONT SUSPENSION ................. 10

YJ FRONT SUSPENSION ................. 13

• Jounce bumpers (used to limit the travel of the
suspension)

The link/coil suspension allows each wheel to adapt
to different road surfaces without greatly affecting
the opposite wheel. Wheels are attached to a hub/
bearings which bolts to the knuckles. The hub/bear­ing is not serviceable and is replaced as a unit.
Steering knuckles pivot on replaceable ball studs at­tached to the axle tube yokes.

The upper and lower suspension arms are different
lengths, with bushings at both ends. They bolt the

Fig. 1 XJ Front Suspension

2 - 2 FRONT SUSPENSION AND AXLE J

axle assembly to the frame. The lower arms uses
shims at the frame mount to allow for adjustment of
caster and pinion angle. The suspension arm travel
(jounce or rebound) is limited through the use of rub­ber bumpers.

Suspension components which use rubber bushings
should be tightened at vehicle ride height. This will
prevent premature failure of the bushing and main­tain ride comfort. Bushings must never be lubricated.

The coil springs control ride quality and maintain
proper ride height. The coil springs mount up in the
fender shield which is part of the unitized body
bracket. A rubber isolator is located between the top
of the spring and the frame. The bottom of the spring
seats on a axle pad and is retained with a clip.

The shock absorbers dampen jounce and rebound of
the vehicle over various road conditions. The top of
the shock absorbers are bolted to the frame. The bot­tom of the shocks are bolted to the axle spring
bracket.

The stabilizer bar is used to minimize vehicle front
sway during turns. The spring steel bar helps to con­trol the vehicle body in relationship to the suspen­sion. The bar extends across the front underside of
the chassis and connects to the frame rails. Links are
connected from the bar to the axle brackets. Stabi­lizer bar mounts are isolated by rubber bushings.

The track bar is used to minimize front axle side­to-side movement. The bar is attached to a frame rail
bracket with a ball stud and isolated with a bushing
at the axle bracket.

Fig. 2 Front Axle— 2WD Vehicles

TUBE AXLE (2WD VEHICLES)

The front axle used on two-wheel drive vehicles is
a one-piece, tubular axle (Fig. 2). The tubular axle
mounts in the same bracketry as does the four-wheel
drive front axle. The steering knuckles and hub bear­ing assemblies are the same as used on the Model 30
drive axle.

YJ VEHICLES

The Wrangler (YJ) front suspension is leaf spring
design comprised of (Fig. 3);

• Drive axle

• Track bar

• Stabilizer bar

• Leaf springs

• Dual-action shock absorbers

• Jounce bumpers (used to limit the travel of the

suspension)

The front suspension uses semi-elliptic multi-leaf
springs mounted on the drive axle. The rearward end
of the springs are mounted to the frame rail hangers
through rubber bushings. The bushings isolate road
noise as the springs move. The forward end of the
springs are attached to the frame with shackles. The
spring and shackles use rubber bushings to isolate
road noise. The shackles allow the springs to change

Fig. 3 YJ Front Suspension

their length as the vehicle moves over various road
conditions. The spring and axle travel (jounce or re­bound) is limited through use of rubber bumpers
mounted on the frame.

Suspension components which use rubber bushings
should be tightened at vehicle ride height. This will
prevent premature failure of the bushing and main­tain ride comfort. The bushings should never be lu­bricated.

J FRONT SUSPENSION AND AXLE 2 - 3

The shocks absorbers dampen jounce and rebound
of the vehicle over various road conditions. The top of
the shock absorbers are bolted to the frame. The bot­tom of the shocks are bolted to the axle bracket.

The stabilizer bar is used to minimize vehicle front
sway during turns. The spring steel bar helps to con­trol the vehicle body in relationship to the suspen­sion. The bar extends across the front underside of
the chassis and connects to the frame rails. Links are
connected from the bar to the axle brackets. Stabi­lizer bar mounts are isolated by rubber bushings.

The track bar is used to minimize front axle side­to-side movement. The track bar is attached to a
frame rail bracket and the axle bracket.

The bar uses bushings at both ends.

FRONT DRIVE AXLE

It is not necessary to remove the complete axle
from the vehicle for routine differential service. If
the differential housing or axle shaft tubes are dam­aged, the complete axle assembly can be removed
and serviced.

For complete drive axle assembly removal and in­stallation refer to Drive Axle Assembly Replacement
in this Group.

The removable cover provides for servicing without
removing axle from vehicle.

The integral type housing, hypoid gear design has
the centerline of the pinion set above the centerline
of the ring gear.

The Model 30 axle has the assembly part number
and gear ratio listed on a tag. The tag is attached to
the housing cover (Fig. 4). Build date identification
codes are stamped on the axle shaft tube cover side.

Fig. 4 Model 30 Differential Cover

XJ and YJ axles are equipped with an optional
A.B.S. brake system. The A.B.S. tone rings are
pressed onto the axle shaft near the hub and
knuckle. For additional information on the A.B.S.
system refer to Group 5, Brakes.

• XJ vehicles use a non-disconnect axle.

• YJ vehicles use a vacuum disconnect axle (Fig. 5).

Fig. 5 Disconnect Feature

STANDARD DIFFERENTIAL OPERATION

The differential gear system divides the torque be­tween the axle shafts. It allows the axle shafts to ro­tate at different speeds when turning corners.

Each differential side gear is splined to an axle
shaft. The pinion gears are mounted on a pinion
mate shaft and are free to rotate on the shaft. The
pinion gear is fitted in a bore in the differential case
and is positioned at a right angle to the axle shafts.

In operation, power flow occurs as follows:

• Pinion gear rotates the ring gear

• Ring gear (bolted to the differential case) rotates

the case

• Differential pinion gears (mounted on the pinion
mate shaft in the case) rotate the side gears

• Side gears (splined to the axle shafts) rotate the
shafts

During straight-ahead driving, the differential pin­ion gears do not rotate on the pinion mate shaft. This
occurs because input torque applied to gears is di­vided and distributed equally between the two side
gears. As a result, the pinion gears revolve with the
pinion mate shaft but do not rotate around it (Fig. 6).

When turning corners, the outside wheel must travel
a greater distance than the inside wheel. This difference
must be compensated for in order to prevent the wheels
from scuffing and skidding through the turn. To accom­plish this, the differential allows the axle shafts to turn
at unequal speeds (Fig. 7). In this instance, the input
torque applied to the pinion gears is not divided
equally. The pinion gears now rotate around the pinion
mate shaft in opposite directions. This allows the side
gear and axle shaft attached to the outside wheel to ro­tate at a faster speed.

2 - 4 FRONT SUSPENSION AND AXLE J

Fig. 6 Differential Operation—Straight-Ahead

Driving

Fig. 7 Differential Operation—On Turns

J FRONT SUSPENSION AND AXLE 2 - 5

FRONT WHEEL ALIGNMENT

INDEX

page page

Alignment Measurements and Adjustments ...... 6

General Information ........................ 5

GENERAL INFORMATION

Front wheel alignment involves the correct posi­tioning of the wheels in relation to the vehicle. The
positioning is accomplished through suspension and
steering linkage adjustments. An alignment is con­sidered essential for efficient steering, good direc­tional stability and to maximize tire wear. The most
important measurements of front end alignment are
caster, camber and toe position.

Routine inspection of the front suspension
and steering components is a good preventative
maintenance practice. Inspection also helps to
ensure safe operation of the vehicle.

• CASTER is the forward or rearward tilt of the
steering knuckle from vertical. Tilting the top of the
knuckle rearward provides positive caster. Tilting the
top of the knuckle forward provides negative caster.
Caster is a directional stability angle which

Pre-Alignment Inspection .................... 6

enables the front wheels to return to a straight
ahead position after turns (Fig. 1).

• CAMBER is the inward or outward tilt of the
wheel relative to the center of the vehicle. Tilting the
top of the wheel inward provides negative camber.
Tilting the top of the wheel outward provides positive
camber. Incorrect camber will cause wear on the in­side or outside edge of the tire (Fig. 1).

• WHEEL TOE POSITION is the difference between
the leading inside edges and trailing inside edges of
the front tires (Fig. 1). Incorrect wheel toe position is
the most common cause of unstable steering and un­even tire wear. The wheel toe position is the final
front wheel alignment adjustment.

• STEERING AXIS INCLINATION ANGLE is mea­sured in degrees and is the angle that the steering
knuckles are tilted (Fig. 1). The inclination angle has
a fixed relationship with the camber angle. It will

Fig. 1 Wheel Alignment Measurements

2 - 6 FRONT SUSPENSION AND AXLE J

not change except when a spindle or ball stud is
damaged or bent. The angle is not adjustable and the
damaged component(s) must be replaced to correct
mis-alignment.

CAUTION:Do not attempt to modify any suspension
or steering component by heating and bending.

PRE-ALIGNMENT INSPECTION

Before starting a front wheel alignment, the follow­ing inspection and necessary corrections must be
completed.

(1) Tires with the same recommended air pressure,
size, and thread wear. Refer to Group 22, Tires And
Wheels for diagnosis information.

(2) Front wheel bearings for wear.

(3) Ball studs, steering linkage pivot points and
steering gear for looseness, roughness, binding or
wear. Refer to Group 19, Steering for additional in­formation.

(4) Front wheels for excessive radial or lateral
runout and unbalance. Refer to Group 22, Tires And
Wheels for diagnosis information.

(5) Suspension components for wear and noise.
Check components for correct torque. Refer to Groups
2 and 3, Suspension and Axle for additional informa­tion.

ever, if steering wheel does not return toward the
center position unassisted, an incorrect caster angle
is probable.

Caster can be adjusted by installing the appropri-

ate size shims (Fig. 2, 3). Changing caster angle

will also change the front propeller shaft angle.
The propeller shaft angle has priority over
caster. Refer to Group 16, Propeller Shafts for
additional information.

Fig. 2 Adjustment—YJ Vehicles

ALIGNMENT MEASUREMENTS AND ADJUSTMENTS

Before each alignment reading, the vehicle should
be jounced (rear first, then front). Grasp each bumper
at the center and jounce the vehicle up and down
several times. Always release the bumper in the
down position. Set the front end alignment to

specifications with the vehicle at its NOR­MALLY RIDE HEIGHT.

CAMBER

The wheel camber angle (Fig. 1) is preset at ZERO
DEGREES (0°). The angle is not adjustable and can­not be altered.

CASTER

The caster angle (Fig. 1) is set at:

• XJ manual transmission, POSITIVE 6.5 DE­GREES (+6.5°).

• XJ automatic transmission, POSITIVE 8.0 DE­GREES (+8.0°).

• YJ all transmissions, POSITIVE 6.0 DEGREES
(+6.0°).

Before checking the caster of the front axle for cor­rect angle. Be sure the axle is not bent or twisted.

Road test the vehicle, and make left and right
turns. If the steering wheel returns to the center po­sition unassisted, the caster angle is correct. How-

Fig. 3 Adjustment—XJ Vehicles

J FRONT SUSPENSION AND AXLE 2 - 7

SUSPENSION AND STEERING SYSTEM DIAGNOSIS

2 - 8 FRONT SUSPENSION AND AXLE J

Fig. 4 Steering Linkage—XJ Vehicles

TOE POSITION—XJ VEHICLES

The wheel toe position adjustment should be the fi­nal adjustment.

(1) Start the engine and turn wheels both ways be­fore straightening the wheels. Secure the steering
wheel with the front wheels in the straight-ahead po­sition.

(2) Loosen the adjustment sleeve clamp bolts (Fig.

4).

(3) Adjust the right wheel toe position with the
drag link. Turn the sleeve until the right wheel is at
specifications. Position the clamp bolts as shown
(Fig. 5) and tighten to 49 Nzm (36 ft. lbs.) torque.

Make sure the toe setting does not change dur­ing clamp tightening.

(4) Adjust the left wheel toe position with the tie
rod. Turn the sleeve until the left wheel is at speci­fications. Position the clamp bolts as shown (Fig. 5)
and tighten to 27 Nzm (20 ft. lbs.) torque. Make sure

the toe setting does not change during clamp
tightening.

(5) Verify the right toe setting.

Fig. 5 Drag Link and Tie Rod Clamp Location

J FRONT SUSPENSION AND AXLE 2 - 9

Fig. 6 Steering Linkage

TOE POSITION—YJ VEHICLES

The wheel toe position should be the final front
wheel alignment adjustment. In all instances follow
the equipment manufacturer’s recommended proce­dure.

(1) Secure the steering wheel with the front wheels
in the straight-ahead position. For vehicles equipped
with power steering, start the engine before straight­ening the wheels.

ALIGNMENT SPECIFICATIONS—XJ VEHICLES

(2) Loosen the adjustment sleeve clamp bolts on

the tie rod (Fig. 6).

YJ Vehicles

The tie rod and adjustment sleeve have both
right and left hand threads to provide equal ad­justment for each wheel.

(3) After the adjustment is completed, position the
tie rod adjustment sleeve clamp bolts as shown.

(4) Tighten the adjustment sleeve clamp bolts to
27 Nzm (20 ft. lbs.) torque.

(5) The steering wheel can be centered by the drag
link. Complete the adjustment. Position the drag link
clamp bolts as shown. Tighten the bolts to 49 Nzm
(36 ft. lbs.) torque.

ALIGNMENT SPECIFICATIONS—YJ VEHICLES

2 - 10 FRONT SUSPENSION AND AXLE J

XJ FRONT SUSPENSION

INDEX

page page

Axle Bushing Replacement ................. 11

Coil Spring ............................. 13

Lower Suspension Arm .................... 11

Service Information ....................... 10

Shock Absorber .......................... 12

SERVICE INFORMATION

CAUTION: Suspension components that use rubber
bushings should be tightened with the vehicle at
the normal height. It is important to have the
springs supporting the weight of the vehicle when
the fasteners are torqued. If the springs are not at
their normal ride position, vehicle ride comfort
could be affected along with premature bushing
wear. Rubber bushings must never be lubricated.

TRACK BAR

REMOVAL

(1) Raise and support the vehicle.
(2) Remove the cotter pin and nut from the ball

stud end at the frame rail bracket (Fig. 1).

A puller tool may be necessary to separate the

ball stud from the frame rail bracket.

(3) Remove the bolt and flag nut from the axle

shaft tube bracket (Fig. 1). Remove the track bar.

Spring and Shock Diagnosis ................ 12

Stabilizer Bar ............................10

Track Bar .............................. 10

Upper Suspension Arm .................... 11

INSTALLATION

(1) Install the track bar at axle tube bracket. Loosely
install the retaining bolt and flag nut (Fig. 1).

(2) It may be necessary to pry the axle assembly
over to install the track bar at the frame rail. Install
track bar at the frame rail bracket. Install the re­taining nut on the stud (Fig. 1).

(3) Remove the supports and lower the vehicle.

(4) Tighten the retaining bolt at the axle shaft
tube bracket to 100 Nzm (74 ft. lbs.) torque.

(5) Tighten the ball stud nut to 81 Nzm (60 ft. lbs.)
torque. Install a new cotter pin.

STABILIZER BAR

REMOVAL

(1) Raise and support the vehicle.

(2) Disconnect the stabilizer bar links from the
axle brackets (Fig. 2).

(3) Disconnect the stabilizer bar from the links.

(4) Disconnect the stabilizer bar clamps from the
frame rails. Remove the stabilizer bar.

Fig. 1 Track Bar

Fig. 2 Stabilizer Bar

J FRONT SUSPENSION AND AXLE 2 - 11

INSTALLATION

(1) Inspect stabilizer bar bushings ( Fig. 2). Re-

place bushings if cracked, cut, distorted, or worn.

(2) Position the stabilizer bar on the frame rail
and install the bushings and clamps. Ensure the bar
is centered with equal spacing on both sides. Tighten
the bolts to 75 Nzm (40 ft. lbs.).

(3) Install the links and grommets onto the stabi­lizer bar and axle brackets (Fig. 2). Tighten the nut
at the connecting links at the axle bracket to 95 Nzm
(70 ft. lbs.) torque.

(4) Tighten the stabilizer bar to connecting link
nut to 36 Nzm (27 ft. lbs.) torque.

(5) Remove the supports and lower the vehicle.

UPPER SUSPENSION ARM

REMOVAL

(1) Raise and support the vehicle.

(2) Remove the upper suspension arm nut and bolt
at the axle bracket (Fig. 3).

(3) Remove the nut and bolt (Fig. 3) at the frame
rail and remove the upper suspension arm.

AXLE BUSHING REPLACEMENT

(1) Remove the upper suspension arm from axle.
Refer to Upper Suspension Arm Removal in this
Group.

(2) Insert Spacer 7932-3 (J-35581-3) around the
bushing in the axle bracket ears (Fig. 4).

(3) Assemble and install Bushing Removal/In­staller (Fig. 4).

(4) Remove the bushing by tightening the hex­head on Long Nut.

Fig. 3 Upper and Lower Suspension Arms

INSTALLATION

(1) Position the upper suspension arm at the axle

and frame rail (Fig. 3).

(2) Install the bolts and finger tighten the nuts

(Fig. 3).

(3) Remove the supports and lower the vehicle.
(4) Tighten the nut at the axle to 75 Nzm (55 ft.

lbs.) torque.

Tighten the nut at the frame bracket to 90 Nzm (66

ft. lbs.) torque.

Fig. 4 Axle Bracket Bushing Removal

For two-wheel drive axles and right side on
Model 30 axle, do not remove Spacer 7932-3 (J­35581-3) at this time.

(5) Position the new bushing on Installer.

(6) Install the bushing by tightening the hex-head
on Long Nut (Fig. 5). Remove Spacer 7932-3 (J­35581-3).

(7) Install the upper suspension arm to axle. Refer
to Upper Suspension Arm Installation in this Group.

LOWER SUSPENSION ARM

REMOVAL

(1) Raise and support the vehicle.

(2) Remove the lower suspension arm nut and bolt
from the axle bracket (Fig. 3).

(3) Remove the nut and bolt (Fig. 3) from the rear
bracket and remove the lower suspension arm.

INSTALLATION

(1) Position the lower suspension arm at the axle
bracket and rear bracket (Fig. 3).

2 - 12 FRONT SUSPENSION AND AXLE J

persists, inspect for damaged and worn bushings, and
attaching components. Repair as necessary.

The shock absorber bushings do not require any
type of lubrication. Do not lubricate the bushings to
reduce bushing noise. Grease or mineral oil-base lu­bricants will deteriorate the bushing rubber.

The shock absorbers are not refillable or adjust­able. If a malfunction occurs, the shock absorber
must be replaced. To test a shock absorber, hold it in
an upright position and force the piston into and out
of the cylinder four or five times. The action through­out each stroke should be smooth and even.

SHOCK ABSORBER

REMOVAL

(1) Remove the nut, retainer and grommet from
the upper stud in the engine compartment (Fig. 6).

(2) Remove the lower nuts and bolts from the axle
bracket (Fig. 6). Remove the shock absorber.

Fig. 5 Axle Bracket Bushing Installation

(2) Install the bolts and finger tighten the nuts

(Fig. 3).

(3) Remove support and lower the vehicle.
(4) Tighten the front and rear nuts to 115 Nzm (85

ft. lbs.) torque.

SPRING AND SHOCK DIAGNOSIS

A squeak noise from the shock absorber can be pro­duced if movement between the rubber bushings and
the metal occurs. This noise can usually be stopped
by tightening the attaching nuts. If the squeak noise

INSTALLATION

(1) Position the lower retainer and grommet on the
upper stud. Insert the shock absorber through the
shock tower hole.

(2) Install the lower bolts and nuts. Tighten nuts
to 19 Nzm (14 ft. lbs.) torque.

(3) Install the upper grommet and retainer on the
stud in the engine compartment. Install the nut and
tighten to 10 Nzm (8 ft. lbs.) torque.

Fig. 6 Coil Spring & Shock Absorber

J FRONT SUSPENSION AND AXLE 2 - 13

COIL SPRING

REMOVAL

(1) Raise and support the vehicle. Position a hy-

draulic jack under the axle to support it.

(2) Remove the wheel if necessary.
(3) Mark and disconnect the front propeller shaft

from the axle.

(4) Disconnect the lower suspension arms from the

axle (Fig. 6).

(5) Disconnect the stabilizer bar link and shock ab-

sorber from the axle.

(6) Disconnect the track bar from the frame rail

bracket.

(7) Disconnect the drag link from the pitman arm.

(8) Lower the axle until the spring is free from the
upper mount. Remove the coil spring clip (Fig. 6) and
remove the spring.

(9) Remove the jounce bumper if necessary from
the upper spring mount (Fig. 6).

YJ FRONT SUSPENSION

INSTALLATION

(1) Install the jounce bumper on the upper spring
mount. Tighten the bolt to 42 Nzm (31 ft. lbs.) torque
(Fig. 6).

(2) Position the coil spring on the axle pad. Install
the spring clip and bolt (Fig. 6). Tighten bolt to 21
Nzm (16 ft. lbs.) torque.

(3) Raise the axle into position until the spring
seats in the upper mount.

(4) Connect the stabilizer bar links and shock ab­sorbers to the axle bracket. Connect the track bar to
the frame rail bracket.

(5) Install the lower suspension arms to the axle.
DO NOT TIGHTEN AT THIS TIME.

(6) Install the front propeller shaft to the axle.

(7) Remove the supports and lower the vehicle.

(8) Tighten lower suspension arms nuts to 115
Nzm (85 ft. lbs.) torque.

INDEX

page page

Leaf Spring ............................. 14

Leaf Spring Eye Bushing Replacement ........15

Service Information ....................... 13

Shock Absorber .......................... 14

SERVICE INFORMATION

It is important to have the springs supporting
the weight of the vehicle when the track bar fas­teners are being torqued. If the springs are not
at their normal ride position, vehicle ride com­fort could be affected along with premature rub­ber bushing wear.

TRACK BAR

REMOVAL

(1) Raise and support the vehicle.

(2) Remove the retaining nuts and bolts (Fig. 1)
from the axle bracket and frame bracket. Remove
track bar.

INSTALLATION

(1) Position track bar at axle shaft tube bracket.
Loosely install the retaining bolt and nut (Fig. 1).

(2) Loosely install the retaining bolt and nut at
the frame bracket.

(3) Remove support and lower vehicle.

(4) Tighten the retaining nut at the axle shaft
tube bracket to 100 Nzm (74 ft. lbs.) torque.

(5) Tighten the retaining nut at the frame bracket
to 142 Nzm (105 ft. lbs.) torque.

Spring and Shock Diagnosis ................ 14

Stabilizer Bar ............................14

Track Bar .............................. 13

Fig. 1 Track Bar

2 - 14 FRONT SUSPENSION AND AXLE J

STABILIZER BAR

REMOVAL

(1) Raise and support the vehicle.

(2) Remove the retaining nut from the connecting
link bolt (Fig. 2).

The shock absorbers are not refillable or adjust­able. If a malfunction occurs, the shock absorber
must be replaced. To test a shock absorber, hold it in
an upright position and force the piston into and out
of the cylinder four or five times. The action through­out each stroke should be smooth and even.

SHOCK ABSORBER

REMOVAL

(1) Remove the nut, retainer and grommet from
the upper stud on the frame bracket (Fig. 3).

(2) Raise and support the vehicle.

(3) Remove the nut, washers and bolt from the
shock absorber lower eye (Fig.3).

Fig. 2 Stabilizer Bar

(3) Remove the retaining clamps from frame rails
(4) Remove the stabilizer bar.

INSTALLATION

(1) Inspect the stabilizer bar bushings (Fig. 2). Re-

place the bushings if cracked, cut, distorted, or worn.

(2) Position the stabilizer bar on the frame. Install
the retaining brackets and fasteners. Tighten bolts to
41 Nzm (30 ft. lbs.) torque.

(3) Install the link upper bolts and nuts. Tighten
the nuts to 61 Nzm (45 ft. lbs.) torque.

(4) Tighten the link spring bracket nuts to 61 Nzm
(45 ft. lbs.) torque.

(5) Lower the vehicle.

SPRING AND SHOCK DIAGNOSIS

A squeak noise from the shock absorber or springs
can be produced if movement between the rubber
bushings and the metal occurs. This noise can usu­ally be stopped by tightening the attaching nuts. If
the squeak noise persists, inspect for damaged and
worn bushings, and attaching components. Repair as
necessary if any of these conditions exist.

The shock absorber bushings do not require any
type of lubrication. Do not lubricate the bushings to
reduce bushing noise. Grease or mineral oil-base lu­bricants will deteriorate the bushing rubber.

Fig. 3 Spring & Shock Absorber

(4) Remove the shock absorber.
(5) Remove the remaining grommet and retainer

from the shock absorber stud.

INSTALLATION

(1) Position the lower retainer and grommet on the
upper stud. Insert the shock absorber through the
shock tower hole.

(2) Install the lower bolts and nuts. Tighten the
nuts to 61 Nzm (45 ft. lbs.) torque.

(3) Install the upper grommet and retainer on the
stud on the frame bracket. Install the nut and
tighten to 12 Nzm (9 ft. lbs.) torque.

LEAF SPRING

REMOVAL

(1) Raise the vehicle.

J FRONT SUSPENSION AND AXLE 2 - 15

(2) Support the vehicle with jack stands placed un-

der the frame.

(3) Position a hydraulic jack under the axle. Raise

the axle to relieve the axle weight from the springs.

(4) Remove the stabilizer bar links attaching nut.
(5) Remove the nuts, the U-bolts and spring

bracket from the axle.

(6) Remove the nut and bolt that attaches the

spring front eye to the shackle (Fig. 3).

(7) Remove the nut and bolt from the spring rear

eye.

(8) Remove the spring from the vehicle.

The spring can be disassembled by removing
the spring clips and the center bolt. If the spring
bushings require replacement, refer to the bush­ing removal and installation procedures.

INSTALLATION

(1) Position the spring front eye in the shackle.
Loosely install the attaching bolt and nut. Do not
tighten at this time.

(2) Position the rear eye in the hanger bracket.
Loosely install the attaching bolt and nut (Fig. 3). Do
not tighten at this time.

(3) Position the axle. Install the spring bracket,
U-bolts and nuts (Fig. 3). Tighten the U-bolt nuts to
122 Nzm (90 ft. lbs.) torque.

(4) Attach the stabilizer bar links.

(5) Remove the hydraulic jack.

(6) Remove the support stands and lower the vehi­cle.

(7) Tighten the front shackle plate nut (Fig. 3) to
135 Nzm (100 ft. lbs.) torque.

(8) Tighten the rear eye bracket nut to 142 Nzm
(105 ft. lbs.) torque.

LEAF SPRING EYE BUSHING REPLACEMENT

(1) Assemble tools shown (Fig. 4). Tighten the nut
located at the socket wrench end of the threaded rod
until the bushing is forced out.

Fig. 4 Spring Eye Bushing Removal

(2) Assemble and align the bushing installation
tools.

(3) Align the bushing with the spring eye and
tighten the nut located at the socket wrench end of
the threaded rod. Tighten until the bushing is forced
into the spring eye.

The bushing must be centered in the spring
eye. The ends of the bushing must be flush or
slightly recessed within the end surfaces of the
spring eye.

2 - 16 FRONT SUSPENSION AND AXLE J

AXLE NOISE/VIBRATION DIAGNOSIS

INDEX

page page

Driveline Snap ........................... 17

Gear and Bearing Noise ................... 16

General Information ....................... 16

GENERAL INFORMATION

Axle bearing problem conditions are usually caused

by:

• Insufficient or incorrect lubricant

• Foreign matter/water contamination

• Incorrect bearing preload torque adjustment

• Incorrect backlash (to tight)

When serviced, the bearings must be cleaned thor­oughly. They should be dried with lint-free shop tow­els. Never dry bearings with compressed air.

This will overheat them and brinell the bearing
surfaces. This will result in noisy operation after
repair.

Axle gear problem conditions are usually the result
of:

• Insufficient lubrication

• Incorrect or contaminated lubricant

• Overloading (excessive engine torque) or exceeding

vehicle weight capacity

• Incorrect clearance or backlash adjustment

Insufficient lubrication is usually the result of a
housing cover leak. It can also be from worn axle
shaft or pinion gear seals. Check for cracks or porous
areas in the housing or tubes.

Using the wrong lubricant will cause overheating
and gear failure. Gear tooth cracking and bearing
spalling are indicators of this.

Axle component breakage is most often the result
of:

• Severe overloading

• Insufficient lubricant

• Incorrect lubricant

• Improperly tightened components

Overloading occurs when towing heavier than rec­ommended loads. Component breakage can occur
when the wheels are spun excessively. Incorrect lu­bricant quantity contributes to breakage. Loose dif­ferential components can also cause breakage.

Incorrect bearing preload or gear backlash will not
result in component breakage. Mis-adjustment will
produce enough noise to cause service repair before a
failure occurs. If a mis-adjustment condition is not
corrected, component failure can result.

Excessive bearing preload may not be noisy. This
condition will cause high temperature which can re­sult in bearing failure.

Low Speed Knock ........................ 17

Vibration ............................... 17

GEAR AND BEARING NOISE

GEAR NOISE

Axle gear noise can be caused by insufficient lubri­cant. Incorrect backlash, tooth contact, or worn/dam­aged gears can cause noise.

Gear noise usually happens at a specific speed
range. The range is 30 to 40 mph, or above 50 mph.
The noise can also occur during a specific type of
driving condition. These conditions are acceleration,
deceleration, coast, or constant load.

When road testing, accelerate the vehicle to the
speed range where the noise is the greatest. Shift
out-of-gear and coast through the peak-noise range.
If the noise stops or changes greatly, check for insuf­ficient lubricant. Incorrect ring gear backlash, or
gear damage can cause noise changes.

Differential side and pinion gears can be checked
by turning the vehicle. They usually do not cause
noise in straight-ahead driving. These gears are
loaded during vehicle turns. If noise does occur dur­ing vehicle turns, the side or pinion gears could be
worn or damaged. A worn pinion gear mate shaft can
also cause a snapping or a knocking noise.

BEARING NOISE

The axle shaft, differential and pinion gear bear­ings can all produce noise when worn or damaged.
Bearing noise can be either a whining, or a growling
sound.

Pinion gear bearings have a constant-pitch noise.
This noise changes only with vehicle speed. Pinion
bearing noise will be higher because it rotates at a
faster rate. Drive the vehicle and load the differen­tial. If bearing noise occurs the pinion rear bearing is
the source of the noise. If the bearing noise is heard
during a coast, front bearing is the source.

Worn, damaged differential bearings usually pro­duce a low pitch noise. Differential bearing noise is
similar to pinion bearing. The pitch of differential
bearing noise is also constant and varies only with
vehicle speed.

Axle shaft bearings produce noise and vibration
when worn or damaged. The noise generally changes
when the bearings are loaded. Road test the vehicle.
Turn the vehicle sharply to the left and to the right.
This will load the bearings and change the noise

J FRONT SUSPENSION AND AXLE 2 - 17

level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.

LOW SPEED KNOCK

Low speed knock is generally caused by a worn
U-joint or by worn side-gear thrust washers. A worn
pinion gear shaft bore will also cause low speed
knock.

VIBRATION

Vibration at the rear of the vehicle is usually
caused by a:

• Damaged drive shaft

• Missing drive shaft balance weight

• Worn, out-of-balance wheels

• Loose wheel lug nuts

• Worn U-joint

• Loose spring U-bolts

• Loose/broken springs

• Damaged axle shaft bearings

• Loose pinion gear nut

• Excessive pinion yoke run out

• Bent axle shaft

Check for loose or damaged front-end components
or engine/transmission mounts. These components

can contribute to what appears to be a rear-end vi­bration. Do not overlook engine accessories, brackets
and drive belts.

All driveline components should be examined be-

fore starting any repair.

Refer to Group 22—Tires And Wheels for addi-

tional information involving vibration diagnosis.

DRIVELINE SNAP

A snap or clunk noise when the vehicle is shifted

into gear (or the clutch engaged), can be caused by:

• High engine idle speed

• Loose engine/transmission/transfer case mounts

• Worn U-joints

• Loose spring mounts

• Loose pinion gear nut and yoke

• Excessive ring gear backlash

• Excessive differential side gear-to-case clearance

The source of a snap or a clunk noise can be deter­mined with the assistance of a helper. Raise the ve­hicle on a hoist with the wheels free to rotate.
Instruct the helper to shift the transmission into
gear. Listen for the noise, a mechanics stethoscope is
helpful in isolating the source of a noise.

2 - 18 FRONT SUSPENSION AND AXLE J

SERVICE DIAGNOSIS

J FRONT SUSPENSION AND AXLE 2 - 19

SERVICE DIAGNOSIS (CONT’D)

2 - 20 FRONT SUSPENSION AND AXLE J

MODEL 30 AXLE AND TUBE AXLE (2WD)

INDEX

page page

Axle Bushing Replacement ................. 32

Axle Shaft — Cardan U-Joint ................25

Axle Specifications ....................... 46

Backlash and Contact Pattern Analysis ........ 44

Cleaning/Inspection ....................... 35

Differential and Pinion Measurement .......... 38

Differential Assembly ...................... 36

Differential Disassembly .................... 34

Differential Installation .....................43

Differential Removal ...................... 32

Differential Shim Pack Measurement and Adjustment
Drive Axle Assembly Replacement—XJ Vehicles . 21
Drive Axle Assembly Replacement—YJ Vehicles . 21

.42

INFORMATION

The housing for Model 30 front axles consists of an
iron center casting (differential housing) with axle
shaft tubes extending from either side. The tubes are
pressed into and welded to the differential housing to
form a one-piece axle housing.

The integral type housing, hypoid gear design has
the centerline of the pinion set above the centerline
of the ring gear.

The axle has a fitting for a vent hose used to re­lieve internal pressure caused by lubricant vaporiza­tion and internal expansion.

The axles are equipped with semi-floating axle
shafts, meaning that loads are supported by the hub
bearings. The axle shafts are retained by nuts at the
hub bearings. The hub bearings are bolted to the
steering knuckle at the outboard end of the axle tube
yoke. The hub bearings are serviced as an assembly.

The axles are equipped with ABS brake sensors.
The sensors are attached to the knuckle assemblies
and tone rings are pressed on the axle shaft. Use

care when removing axle shafts as NOT to dam­age the tone wheel or the sensor.

The stamped steel cover provides a means for in­spection and servicing the differential.

The Model 30 axle has the assembly part number
and gear ratio listed on a tag. The tag is attached to
the housing cover. Build date identification codes are
stamped on the axle shaft tube cover side.

The differential case is a one-piece design. The dif­ferential pinion mate shaft is retained with a roll
pin. Differential bearing preload and ring gear back­lash is adjusted by the use of shims (select thick­ness). The shims are located between the differential
bearing cones and case. Pinion bearing preload is set
and maintained by the use of collapsible spacer.

PINION GEAR DEPTH MEASUREMENT WITH
PINION GAUGE SET 6774, Pinion Block 6733 and
Dial Indicator C-3339 is performed when;

Final Assembly .......................... 44

Hub Bearing and Axle Shaft ................ 24

Information ............................. 20

Inner Axle Shaft Oil Seal Replacement ........ 33

Lubricant Change ........................ 22

Lubricant Specifications .................... 20

Pinion Gear Assembly/Installation ............ 40

Pinion Gear Depth Information .............. 37

Pinion Removal/Disassembly ................ 34

Pinion Seal Replacement .................. 23

Steering Knuckle and Ball Studs ............. 30

Vacuum Disconnect Axle — YJ Vehicles ....... 26

• Axle/differential housing is being replaced

• Original pinion depth shim pack is lost or mis-

placed

• Replacing the differential case

• Original differential bearing shim pack is lost or

misplaced

COMMAND-TRAC—YJ VEHICLES

The Command-Trac system is a vacuum disconnect
axle. The system has a two-piece axle shaft coupled
together by a shift collar. For two-wheel drive oper­ation, the vacuum motor and shift fork disengages
the axle shaft splines. For four-wheel drive opera­tion, the vacuum motor and shift fork engages the
splines.

SELEC-TRAC—XJ VEHICLES

The Selec-Trac system is a non-disconnect axle.
Shifting from two-wheel to four-wheel drive is at the
transfer case.

For XJ vehicles equipped with Selec-Trac and
ABS brake system, refer to Group 5—Brakes for ad­ditional service information.

LUBRICANT SPECIFICATIONS

Multi-purpose, hypoid gear lubricant should be
used for Model 30 axles. The lubricant should have
MIL-L-2105C and API GL 5 quality specifications.
MOPARt Hypoid Gear Lubricant conforms to both of
these specifications.

• The factory fill for the Model 30 axle is SAE 75W
gear lubricant. Do not use heavier weight lubri-

cant, this will cause axle engagement difficulties.

• The factory installed lubricant quantity for the
NON-DISCONNECT TYPE AXLE is 5061 fluid oz..

• The factory installed lubricant quantity for the
VACUUM-DISCONNECT TYPE AXLE is 5661 fluid
oz..

J FRONT SUSPENSION AND AXLE 2 - 21

Refer to Group 0, Lubrication and Maintenance for
additional information regarding temperature range,
viscosity and fluid level.

CAUTION: If the axle is submerged in water, the lu­bricant must be replaced immediately to avoid the
possibility of premature axle failure.

DRIVE AXLE ASSEMBLY REPLACEMENT—XJ
VEHICLES

REMOVAL

(1) Raise the vehicle and position support stands
under the frame rails slightly in behind the lower
suspension arm frame brackets.

(2) Remove the front wheels.

(3) Remove the brake components and ABS brake
sensor (if equipped). Refer to Group 5—Brakes.

(4) On 4WD vehicles, disconnect the axle vent
hose.

(5) On 4WD vehicles, mark the drive shaft yoke
and axle pinion yoke for alignment reference. Discon­nect the drive shaft from the axle.

(6) Disconnect the stabilizer bar link at the axle
bracket.

(7) Disconnect the shock absorbers from axle
bracket.

(8) Disconnect the track bar from the axle bracket.

(9) Disconnect the tie rod and drag link from the
steering knuckle. Disconnect the steering dampener
from the axle bracket.

(10) Support the axle with a hydraulic jack under
the differential.

(11) Disconnect the upper and lower suspension
arms from the axle bracket.

(12) Lower the jack enough to remove the axle.
The coil springs will drop with the axle.

(13) Remove the coil springs from the axle bracket.

INSTALLATION

CAUTION: All suspension components that use rub­ber bushings should be tightened with the vehicle
at the ride height. It is important to have the
springs supporting the weight of the vehicle when
the fasteners are torqued. If the springs are not at
their normal ride position, vehicle ride comfort
could be affected along with premature rubber
bushing wear. Rubber bushings must never be lu­bricated.

(1) Install the springs and retainer clip. Tighten
the retainer bolts to 21 Nzm (16 ft. lbs.) torque.

(2) Support the axle on a hydraulic jack under the
differential. Position the axle under the vehicle.

(3) Raise the axle with a floor jack and align it
with the spring pads.

(4) Position the upper and lower suspension arm at
the axle bracket. Install bolts and nuts finger
tighten.

(5) Connect the track bar to the axle bracket and
install the bolt. Do not tighten at this time.

It is important that the springs support the
weight of the vehicle when the track bar is con­nected. If the springs are not at their usual po­sition, the vehicle ride comfort could be affected.

(6) Install the shock absorber and tighten the bolt
to 19 Nzm (14 ft. lbs.) torque.

(7) Install the stabilizer bar link to the axle
bracket. Tighten the nut to 95 Nzm (70 ft. lbs.)
torque.

(8) Install the drag link and tie rod to the steering
knuckles and tighten the nuts to 47 Nzm (35 ft. lbs.)
torque. Install the steering dampener to the axle
bracket and tighten the nut to 75 Nzm (55 ft. lbs.)
torque.

(9) Install the brake components and ABS brake
sensor (if equipped). Refer to Group 5—Brakes.

(10) On 4WD vehicles, connect the vent hose to the
tube fitting.

(11) On 4WD vehicles, align the reference marks
and connect the drive shaft to the axle yoke. Tighten
the U-joint clamp bolts to 19 Nzm (14 ft. lbs.) torque.

(12) Check differential lubricant and add if neces­sary.

(13) Install the wheel and tire assemblies.

(14) Remove the supports and lower the vehicle.

(15) Tighten the upper suspension arm nuts to 75
Nzm (55 ft. lbs.) torque. Tighten the lower suspension
arm nuts to 115 Nzm (85 ft. lbs.) torque.

(16) Tighten the track bar bolt at the axle bracket
to 100 Nzm (74 ft. lbs.) torque.

(17) Check the front wheel alignment.

DRIVE AXLE ASSEMBLY REPLACEMENT—YJ
VEHICLES

REMOVAL

(1) Raise the vehicle and position support stands
under the frame rails slightly behind the spring
frame brackets.

(2) Remove the front wheels.

(3) Remove the brake components and ABS brake
sensor (if equipped). Refer to Group 5—Brakes.

(4) Disconnect the axle vent hose and axle shift
motor vacuum harness.

(5) Mark the drive shaft yoke and axle pinion yoke
for alignment reference. Disconnect the drive shaft
from the axle.

(6) Disconnect the stabilizer bar link at the axle
bracket.

(7) Disconnect the shock absorbers from axle
bracket.

(8) Disconnect the track bar from the axle bracket.

2 - 22 FRONT SUSPENSION AND AXLE J

(9) Disconnect the tie rod from the steering
knuckle. Disconnect the steering dampener from the
axle bracket.

(10) Support the axle with a hydraulic jack under
the differential. Raise the axle just enough to relieve
the axle weight from the springs.

(11) Remove the spring U-bolts from the plate
brackets.

(12) Loosen BUT DO NOT REMOVE the bolts that
attach the spring rear pivot at the frame rail brack­ets. This will allow the springs to pivot without bind­ing on the bushings.

(13) Disconnect shackle from the springs and lower
the springs to the surface.

(14) Lower the jack enough to remove the axle.

INSTALLATION

CAUTION: All suspension components that use rub­ber bushings should be tightened with the vehicle
at the normal height. It is important to have the
springs supporting the weight of the vehicle when
the fasteners are torqued. If the springs are not at
their normal ride position, vehicle ride comfort
could be affected along with premature rubber
bushing wear. Rubber bushings must never be lu­bricated.

(1) Support the axle on a hydraulic jack under the
differential. Position the axle under the vehicle.

(2) Raise the springs and install the spring shackle
bolts. Do not tighten at this time.

(3) Lower the axle and align the spring center
bolts with the locating holes in the axle pads and
plate brackets.

(4) Install the spring U-bolts through the plate
brackets and tighten to 122 Nzm (90 ft. lbs.) torque.

(5) Connect the track bar to the axle bracket and
install the bolt. Do not tighten at this time.

It is important that the springs support the
weight of the vehicle when the track bar is con­nected. If the springs are not at their usual po­sition, the vehicle ride comfort could be affected.

(6) Install the shock absorber and tighten the nut
to 61 Nzm (45 ft. lbs.) torque.

(7) Install the stabilizer bar link to the axle
bracket. Tighten the nut to 61 Nzm (45 ft. lbs.)
torque.

(8) Install the tie rod to the steering knuckles and
tighten the nuts to 47 Nzm (35 ft. lbs.) torque. Install
the steering dampener to the axle bracket and
tighten the bolt to 75 Nzm (55 ft. lbs.) torque.

(9) Install the brake components and ABS brake
sensor (if equipped). Refer to Group 5—Brakes.

(10) Connect the vent hose to the tube fitting and
axle shift motor vacuum harness.

(11) Align the reference marks and connect the
drive shaft to the axle yoke. Tighten the U-joint
clamp bolts to 19 Nzm (14 ft. lbs.) torque.

(12) Check differential lubricant and add if neces­sary.

(13) Install the wheel and tire assemblies.

(14) Remove the supports and lower the vehicle.

(15) Tighten the spring rear pivot bolt/nut to 142
Nzm (105 ft. lbs.) torque. Tighten the spring shackle
bolt/nut to 135 Nzm (100 ft. lbs.) torque.

(16) Tighten the track bar nut at the axle bracket
to 100 Nzm (74 ft. lbs.) torque.

(17) Check the front wheel alignment.

LUBRICANT CHANGE

The gear lubricant will drain quicker if the vehicle
has been recently driven.

(1) Raise and support the vehicle.

(2) Remove the lubricant fill hole plug from the
differential housing cover.

(3) Remove the differential housing cover and
drain the lubricant from the housing.

(4) Clean the housing cavity with a flushing oil,
light engine oil or lint free cloth. Do not use water,

steam, kerosene or gasoline for cleaning.

(5) Remove the sealant from the housing and cover
surfaces. Use solvent to clean the mating surfaces.

(6) Apply a bead of MOPARt Silicone Rubber Seal­ant to the housing cover (Fig. 1). Allow the sealant

to cure for a few minutes.

Fig. 1 Typical Housing Cover With Sealant

Install the housing cover within 5 minutes af­ter applying the sealant. If not installed the seal­ant must be removed and another bead applied.

J FRONT SUSPENSION AND AXLE 2 - 23

(7) Install the cover and any identification tag.
Tighten the cover bolts in a criss-cross pattern to 41
Nzm (30 ft. lbs.) torque.

(8) Refill the differential with MOPARt Hypoid
Gear Lubricant within 13 mm (1/2 in.) below the fill
plug hole.

(9) Install the fill hole plug and lower the vehicle.

PINION SEAL REPLACEMENT

CAUTION: The following procedures must be used
so the correct pinion bearing preload torque is re­tained. If this procedure is not followed, the result
can be premature failure of the rear axle.

REMOVAL

(1) Raise and support the vehicle.

(2) Remove wheel and tire assemblies.

(3) Mark the propeller shaft yoke and pinion yoke
for installation alignment reference.

(4) Remove the propeller shaft from the yoke.

(5) Rotate the pinion gear three or four times.

Make sure brakes are not dragging during this
procedure.

(6) Measure the amount of torque (in Newton­meters or inch-pounds) necessary to rotate the pinion
gear with a torque wrench. Note the torque for in­stallation reference. It must be known to properly

adjust the pinion gear bearing preload torque
after seal installation.

(7) Remove the pinion yoke nut and washer. Use
Remover C-452 and Wrench C-3281 to remove the
pinion yoke (Fig. 2).

(8) Mark the positions of the yoke and pinion gear
for installation alignment reference.

(9) Use Remover W-251 to remove the pinion gear

seal (Fig. 3).

Fig. 3 Seal Removal

INSTALLATION

(1) Apply a light coating of gear lubricant on the
lip of pinion seal. Install seal with Installer W-147-E
and Handle C-4171 (Fig. 4).

Fig. 2 Pinion Yoke Removal

Fig. 4 Pinion Seal Installation

(2) Align the reference marks and install yoke on
the pinion gear with Installer W-162-D.

(3) Install a new pinion nut on pinion shaft.

Tighten the nut only enough to remove the shaft
end play.

2 - 24 FRONT SUSPENSION AND AXLE J

CAUTION: Never loosen the pinion gear nut to de­crease the pinion gear bearing preload torque. If the
specified preload torque is exceeded, a new col­lapsible spacer must be installed. The torque se­quence will have to be repeated.

(4) Install a socket and inch-pound torque wrench

on the pinion nut.

(5) Rotate the shaft with the torque wrench and

note the torque.

Required preload torque is the amount re­corded during removal plus an additional 0.56
Nzm (5 in. lbs.).

(6) Use Flange Wrench C-3281 to retain the yoke
and shaft (Fig. 5). Tighten the shaft nut in very
small increments.

(7) Continue tightening the shaft nut in small in­crements until the correct bearing preload torque is
attained.

(8) Align the installation reference marks and at­tach the propeller shaft to the yoke.

(9) Add API grade GL 5 hypoid gear lubricant to
the differential housing, if necessary.

(10) Install wheel and tire assemblies.

(11) Remove support and lower the vehicle.

HUB BEARING AND AXLE SHAFT

REMOVAL

(1) Raise and support the vehicle.

(2) Remove the wheel and tire assembly.

(3) Remove the brake components from the axle,
refer to Group 5, Brakes.

(4) Remove the cotter pin, nut retainer and axle
hub nut (Fig. 6).

(5) Remove the hub to knuckle bolts (Fig. 6). Re­move the hub from the steering knuckle and axle
shaft.

(6) Remove the disc brake rotor shield from the
bearing carrier (Fig. 6).

(7) On disconnect axles, remove vacuum shift mo­tor housing. Refer to Vacuum Disconnect Axle in this
section.

(8) Remove the axle shaft from the housing. Avoid

damaging the axle shaft oil seals in the differen­tial.

Fig. 5 Tightening Pinion Shaft Nut

Fig. 6 Hub, Knuckle and Axle Shaft

J FRONT SUSPENSION AND AXLE 2 - 25

INSTALLATION

(1) Thoroughly clean the axle shaft (Fig. 6) and ap­ply a thin film of Mopar Wheel Bearing Grease to
the shaft splines, seal contact surface, hub bore.

(2) Install the axle shaft into the housing and dif­ferential side gears. Avoid damaging the axle shaft
oil seals in the differential.

(3) Install the hub bearing and brake dust shield
to the knuckle.

(4) Install the hub to knuckle bolts and tighten to
102 Nzm (75 ft. lbs.) torque.

(5) Install the hub washer and nut. Tighten the
hub nut to 237 Nzm (175 ft. lbs.) torque. Install the
nut retainer and a new cotter pin (Fig. 6).

(6) Install the brake components, refer to Group 5,
Brakes.

(7) Install the wheel and tire assembly.

(8) Remove support and lower the vehicle.

AXLE SHAFT— CARDAN U-JOINT

DISASSEMBLY

Single cardan U-joints are not serviceable. If defec­tive, they must be replaced as a unit. If the bearings,
seals, spider or bearing caps are damaged or worn,
replace the complete U-joint.

(2) Locate a socket that is larger in diameter than
the bearing cap. Place the socket (receiver) against
the yoke and around the perimeter of the bearing cap
to be removed. Locate a socket that is smaller in di­ameter than the bearing cap. Place the socket (driv­er) against the opposite bearing cap. Position the
yoke with the sockets in a vise (Fig. 8).

CAUTION: Clamp only the forged portion of the
yoke in the vise. Also, to avoid distorting the yoke,
do not over tighten the vise jaws.

(1) Remove the bearing cap retaining snap rings

(Fig. 7).

Fig. 7 Axle Shaft Outer U-Joint

It can be helpful to saturate the bearing caps

with penetrating oil prior to removal.

Fig. 8 Yoke Bearing Cap Removal

(3) Compress the vise jaws to force the bearing cap
into the larger socket (receiver).

(4) Release the vise jaws. Remove the sockets and
bearing cap that was partially forced out of the yoke.

(5) Repeat the above procedure for the remaining
bearing cap.

(6) Remove the remaining bearing cap, bearings,
seals and spider from the propeller shaft yoke.

CLEANING AND INSPECTION

(1) Clean all the U-joint yoke bores with cleaning
solvent and a wire brush. Ensure that all the rust
and foreign matter are removed from the bores.

(2) Inspect the yokes for distortion, cracks and
worn bearing cap bores.

(3) Replace the complete U-joint if any of the com­ponents are defective.

ASSEMBLY

(1) Pack the bearing caps 1/3 full of wheel bearing
lubricant. Apply extreme pressure (EP), lithium-base
lubricant to aid in installation.

(2) Position the spider in the yoke. Insert the seals
and bearings. Tap the bearing caps into the yoke
bores far enough to hold the spider in position.

2 - 26 FRONT SUSPENSION AND AXLE J

(3) Place the socket (driver) against one bearing
cap. Position the yoke with the socket wrench in a
vise.

(4) Compress the vise to force the bearing caps into
the yoke. Force the caps enough to install the retain­ing clips.

(5) Install the bearing cap retaining clips.

(6) Install the axle shaft, refer to Hub Bearing and
Axle Shaft installation.

VACUUM DISCONNECT AXLE — YJ VEHICLES

VACUUM CONTROL SYSTEM

The disconnect axle control system consists of;

• Vacuum control switch on the transfer case

• Air vent filter

• Shift motor

• Indicator switch

• Vacuum switch

• Check valve

• Vacuum harness (Fig. 9, 10)

Refer to Group 21—Transmissions for addi­tional information involving the Command-Trac
System Transfer Case.

Fig. 9 Vacuum Control System

Fig. 10 Vacuum Hose Routing

J FRONT SUSPENSION AND AXLE 2 - 27

DISCONNECT AXLE/SHIFT MOTOR DIAGNOSIS

2 - 28 FRONT SUSPENSION AND AXLE J

DISCONNECT AXLE/SHIFT MOTOR DIAGNOSIS (CONT’D)

J FRONT SUSPENSION AND AXLE 2 - 29

SHIFT MOTOR — REMOVAL/DISASSEMBLY

(1) Disconnect the vacuum and wiring connector
from the shift housing.

(2) Remove indicator switch.

(3) Remove the shift motor housing cover, gasket
and shield from the housing (Fig. 11).

Fig. 11 Shift Motor Housing and Shift Collar

(4) Remove the E-clips from the shift motor hous­ing and shaft. Remove shift motor and shift fork
from the housing (Fig. 12).

(3) Install the E-clips on the shift motor shaft and

housing.

(4) Install the shift motor housing gasket and

cover. Ensure the shift fork is correctly guided

into the shift collar groove.

(5) Install the shift motor housing shield and at­taching bolts. Tighten the bolts to 11 Nzm (101 in.
lbs.) torque.

(6) Add 148 ml (5 ounces) of API grade GL 5 hy­poid gear lubricant to the shift motor housing. Add
lubricant through indicator switch mounting hole.

(7) Install indicator switch, electrical connector
and vacuum harness.

INTERMEDIATE AXLE SHAFT—REMOVAL/
DISASSEMBLY

Service to the Disconnect axle seals and bearing re­quire the use of Tool Set 6288 (J34659) and Seal In­staller 6228.

(1) Remove the vacuum motor housing. Refer to
Shift Motor Removal in this section.

(3) Remove the outer axle shaft. Refer to Hub
Bearing and Axle Shaft in this section.

(4) Remove shift collar and intermediate axle
shaft.

(5) Remove the inner axle shaft seal from the shift
motor housing (Fig. 13).

Fig. 12 Vacuum Shift Motor Components

(5) Remove the O-ring seal from the shift motor

shaft.

(6) Clean and inspect all components. If any com­ponent is excessively worn or damaged, it should be
replaced.

ASSEMBLY/INSTALLATION

(1) Install a new O-ring seal on the shift motor
shaft.

(2) Insert the shift motor shaft through the hole in
the housing and shift fork. The shift fork offset
should be toward the differential.

Fig. 13 Axle Shaft Inner Seal Removal

(6) Remove the intermediate axle shaft bearing

(Fig. 14).

ASSEMBLY/INSTALLATION

(1) Position the bearing on installation tool. Seat

the bearing in the housing bore (Fig. 15).

(2) Clean the inside perimeter of the axle shaft

tube with fine crocus cloth.

(3) Apply a light film of oil to the inside lip of the

new axle shaft seal.

(4) Install the inner axle seal (Fig. 16, 17).

The axle shaft seal primary installation tool

6228-1 will only force the seal partially into the

2 - 30 FRONT SUSPENSION AND AXLE J

Fig. 14 Bearing Removal Tool Installed

Fig. 15 Intermediate Shaft Bearing Installation

axle shaft tube bore. The axle shaft seal second­ary installation tool 6228-3 must be used to com­pletely seat the seal in the axle shaft tube bore.
After seal installation, inspect that the seal is
NOT distorted or cocked in the tube.

Fig. 17 Secondary Installation of Seal (Step Two)

(5) Insert the intermediate axle shaft into the dif-

ferential side gear.

(6) Install the shift collar on the splined end of the

intermediate axle shaft.

(7) Lubricate the splined end of the intermediate

axle shaft with multi-purpose lubricant (Fig. 18).

Fig. 16 Primary Installation of Seal (Step One)

Fig. 18 Shift Collar Installation

CAUTION: Apply all-purpose lubricant to the axle
shaft splines to prevent damage to the seal during
axle shaft installation.

(8) Insert the axle shaft into the tube. Engage the
splined-end of the shaft with the shift collar. Refer to
Hub Bearing and Axle Shaft in this section.

(9) Install the vacuum motor housing. Refer to
Shift Motor Installation in this section.

STEERING KNUCKLE AND BALL STUDS

Ball Stud service procedures below require removal
of the hub bearing and axle shaft. Removal and in­stallation of upper and lower ball stud requires use
of Tool Kit 6289 (J34503-A).

J FRONT SUSPENSION AND AXLE 2 - 31

KNUCKLE REMOVAL

(1) Remove hub bearing and axle shaft refer to the
Removal procedure.

(2) Disconnect the tie-rod or drag link end from
the steering knuckle arm. Remove the ABS sensor
wire and bracket from knuckle.

(3) Remove the cotter pins from the upper and
lower ball studs. Remove the upper and lower ball
stud nuts.

(4) Strike the steering knuckle with a brass ham­mer to loosen. Remove knuckle from axle tube yokes
(Fig. 19).

UPPER BALL STUD REPLACEMENT

(1) Position tools as shown to remove and install
ball stud (Fig. 20).

LOWER BALL STUD REPLACEMENT

(1) Position tools as shown to remove and install
ball stud (Fig.21). Because there are two different de­signs for the lower ball studs try both installers for
proper fit.

Fig. 19 Steering Knuckle Removal/Installation

The lower ball stud has two different designs. For
this reason installer 6752 will also be needed. Check
installers for proper fit.

KNUCKLE INSTALLATION

(1) Position the steering knuckle on the ball studs.
(2) Install and tighten the bottom retaining nut to

109 Nzm (80 ft. lbs.) torque. Install new cotter pins.

(3) Install and tighten the top retaining nut to 101

Nzm (75 ft. lbs.) torque. Install new cotter pin.

Fig. 20 Upper Ball Stud Remove/Install

2 - 32 FRONT SUSPENSION AND AXLE J

Fig. 21 Lower Ball Stud Remove/Install

(4) Install the Hub Bearing and Axle Shaft accord­ing to the installation procedure.

(5) Reconnect the tie-rod or drag link end onto the
steering knuckle arm. Install the ABS sensor wire
and bracket to the knuckle, refer to Group 5 —
Brakes.

AXLE BUSHING REPLACEMENT

Refer to Axle Bushing Replacement in the Front
Suspension section.

DIFFERENTIAL REMOVAL

To service the differential the axle assembly and
axle shafts must be removed. Refer to the removal
procedures in this Group.

(1) Note the installation reference letters stamped
on the bearing caps and housing machined sealing
surface (Fig. 22).

(2) Remove the differential bearing caps.

(3) Position Spreader W-129-B with the tool dowel
pins seated in the locating holes (Fig. 23). Install the
holddown clamps and tighten the tool turnbuckle fin­ger-tight.

(4) Install a pilot stud at the left side of the differ­ential housing. Attach Dial Indicator to housing pilot
stud. Load the indicator plunger against the opposite
side of the housing (Fig. 26) and zero the indicator.

CAUTION:Do not spread over 0.38 mm (0.015 in). If

Fig. 22 Bearing Cap Identification

the housing is over-separated, it could be distorted
or damaged.

(5) Separate the housing enough to remove the
case from the housing. Measure the distance with the
dial indicator (Fig. 23).

(6) Remove the dial indicator.

(7) Pry the differential case loose from the hous­ing. To prevent damage, pivot on housing with the
end of the pry bar against spreader (Fig. 24).

J FRONT SUSPENSION AND AXLE 2 - 33

Fig. 23 Spread Differential Housing

Fig. 24 Differential Removal

(8) Remove the case from housing. Mark or tag
bearing cups indicating which side they were re­moved. Remove spreader from housing.

INNER AXLE SHAFT OIL SEAL REPLACEMENT

Fig. 25 Axle Seal Installation

(2) Install the inner axle seal on Tool 6228-1 (Fig.

26).
(3) Thread the reverse side of Installer 6228-1

tightly onto the threaded rod tool (Fig. 26).

(4) Press the seal into position.

SELECT-TRAC

(1) Remove the inner axle shaft seals with a pry

bay.

(2) Install oil seals with Discs 6764 and Turn­buckle D-112-A (Fig. 25). Tighten tool until disc bot­toms in housing.

COMMAND-TRAC— LEFT-SIDE

(1) Remove the inner axle shaft seal with a pry
bay.

Fig. 26 Left Side Seal Installation

2 - 34 FRONT SUSPENSION AND AXLE J

Fig. 28 Ring Gear Removal

Fig. 27 Differential Bearing Removal

DIFFERENTIAL DISASSEMBLY

(1) Remove the bearings from the differential case
with Press C-293-PA, Plug C-293-3, Adapter
C-293-39 (Fig. 27).

Place adapter rings so they do not damage the
bearing cage.

(2) Remove bearing shims from case hubs and
mark them (with hub identity) for assembly refer­ence. Record the thickness of the shims.

(3) Clamp the differential case in a vise equipped
with soft jaws. Remove and discard the ring gear
bolts. Tap the ring gear with a rawhide or plastic
mallet and remove (Fig. 28).

(4) Use a drift to remove the pinion gear mate
shaft lock pin (Fig. 29).

(5) Remove the mate shaft with a drift and ham­mer (Fig. 30).

(6) Rotate the differential side gears and remove
the pinion mate gears and thrust washers (Fig. 31).

(7) Remove the differential side gears and thrust
washers.

(8) Remove the case from the vise.

Fig. 29 Mate Shaft Lock Pin Removal

PINION REMOVAL/DISASSEMBLY

(1) Remove the pinion yoke nut and washer. Use
Remover C-452 and Wrench C-3281 to remove the
pinion yoke (Fig. 32).

Fig. 30 Mate Shaft Removal

J FRONT SUSPENSION AND AXLE 2 - 35

Fig. 31 Pinion Mate Gear Removal

Fig. 32 Pinion Yoke Removal

(2) Remove the pinion gear seal with a slide ham­mer or pry out with bar.

(3) Drive out pinion gear from housing with raw­hide or plastic hammer (Fig. 33). Catch the pinion
with your hand to prevent it from falling and being
damaged. This will damage the front bearing roll-

ers and bearing cup. The front bearing and cup
must be replaced. Remove and discard collapsible

preload spacer (Fig. 34).

(4) Remove front bearing from housing.

(5) Remove the front pinion bearing cup with Re­mover D-147 and Handle C-4171 (Fig. 35).

(7) Remove the rear bearing cup from housing
(Fig. 36). Use Remover D-149 and Handle C-4171.

(8) Remove the inner bearing from the pinion with
Puller C-293-PA and Adapter C-293-39 (Fig. 37).

Fig. 33 Remove Pinion Gear

Fig. 34 Collapsible Preload Spacer

Place adapter rings so they do not damage the

bearing cage.

(9) Remove the oil slinger from the pinion gear

shaft. Save the slinger it is used as select shim

for pinion depth.

CLEANING/INSPECTION

Wash differential components with cleaning sol-

vent and dry with compressed air. Do not steam

clean the differential components.

2 - 36 FRONT SUSPENSION AND AXLE J

Fig. 35 Front Bearing Cup Removal

Fig. 36 Rear Bearing Cup Removal

Wash bearings with solvent and towel dry, do not
dry with compressed air. Cup and bearing must be

replaced as a matched sets only.

Clean the axle shaft tubes with a clean cloth.

Inspect for;

• Smooth appearance with no broken/dented surfaces
on the bearing rollers or the roller contact surfaces.

• Bearing cups must not be distorted or cracked.

• Machined surfaces should be smooth and without

any raised edges.

• Raised metal on shoulders of cup bores should be
removed with a hand stone.

Fig. 37 Inner Bearing Removal

• Wear or damage to pinion gear mate shaft, pinion
gears, side gears and thrust washers. Replace as a
matched set only.

• Worn or chipped teeth to ring and pinion gears.

• Damaged bolt threads to ring gear. Replaced as a

matched set only.

• Pinion yoke for cracks, worn splines, pitted areas,
and a rough/corroded seal contact surface. Repair or
replace the as necessary.

DIFFERENTIAL ASSEMBLY

ASSEMBLY

(1) Install the following components in the differ-

ential case (Fig. 38).

• Differential side gears and thrust washers

• Pinion gears and thrust washers

• Pinion gear mate shaft (align holes in shaft and

case)

(2) Install and seat the locking roll pin in the dif­ferential case and mate shaft with a punch and ham­mer (Fig. 38). Peen metal part of case over pin in two
places 180 degrees apart.

If replacement gears and thrust washers were
installed, it is not necessary to measure the gear
backlash. Correct fit is due to close machining
tolerances during manufacture.

(3) Invert the differential case and start two ring
gear bolts. This will provide case-to-ring gear bolt
hole alignment.

(4) Install new ring gear bolts and alternately
tighten to 95-122 Nzm (70-90 ft. lbs.) torque (Fig. 39).

(5) Lubricate all differential components with hy­poid gear lubricant.

J FRONT SUSPENSION AND AXLE 2 - 37

pinion is 92.1 mm (3.625 inches) for Model 30 axles
(Fig. 41). The standard depth provides the best teeth
contact pattern.

Fig. 40 Pinion Gear ID Numbers

THE BUTTON END ON THE PINION GEAR

Fig. 38 Mate Shaft Pin Installation

HEAD IS NO LONGER A MACHINED-TO-SPECI­FICATIONS SURFACE. DO NOT USE THIS SUR­FACE FOR PINION DEPTH SET-UP OR
CHECKING (Fig. 41).

Fig. 39 Ring Gear Bolt Installation

PINION GEAR DEPTH INFORMATION

Ring and pinion gears are supplied as matched sets
only. The identifying numbers for the ring and pin­ion gear are etched into the face of each gear (Fig.

40). A plus (+) number, minus (-) number or zero (0)
is etched into the face of the pinion gear. This num­ber is the amount (in thousandths of an inch) the
depth varies from the standard depth setting of a
pinion etched with a (0). The standard setting from
the centerline of the ring gear to the back face of the

Fig. 41 Pinion Gear Head

Compensation for depth variance is achieved by a
selected thickness oil slinger (production) or shims
(service). The slinger is placed between the inner
pinion bearing cone and gear head (Fig. 42). The
shim pack is placed under the inner (rear) bearing
cup for service. To change the pinion adjustment,
shims are available in thicknesses of 0.003, 0.005,
and 0.010 inch. The oil slinger or baffle must be

measured and the thickness included with the
total shim pack.

New gear set: note the depth variance etched
into both the original and the replacement pin­ion gear. Add or subtract the thickness of the

2 - 38 FRONT SUSPENSION AND AXLE J

new pinion is (-) 2, intersecting figure is (-)0.001 inch
(0.025mm). Subtract this amount from original shim.

Refer to the Pinion Gear Depth Variance Chart.

DIFFERENTIAL AND PINION MEASUREMENT

DIFFERENTIAL ZERO END PLAY
MEASUREMENT

(1) Place Master Differential Bearing D-134
(D-348) on the case hubs (Fig. 43) and install differ­ential case into housing.

(2) Install a pilot stud at the right side of housing.
Attach Dial Indicator to the pilot stud. Load indica­tor plunger against the back of the ring gear (Fig.

44).

(3) Insert a small pry bar between the bearing cap
and left side of differential case. Pry the case as far
as possible to right side (Fig. 44). Zero the dial indi­cator pointer.

(4) Pry the case to left side and record the travel
distance.

Fig. 42 Shim Locations

original depth shims to compensate for the dif­ference in the depth variances. Refer to the
Depth Variance charts.

Note where Old and New Pinion Marking columns
intersect. Intersecting figure represents plus or mi­nus amount needed.

For example, if old pinion is plus (+) 1 and the
new pinion is minus (-) 3, intersecting figure is
(+)0.004 inch (0.10mm). Add this amount to the
original shim. Or if the old pinion is (-) 3 and the

The measurement above is the shim thickness
necessary for case zero end-play. The total
thickness will be determined during the ring
gear backlash adjustment.

(5) Remove indicator, pilot stud and differential
case from housing.

PINION GEAR DEPTH MEASUREMENT

Pinion gear depth measurement is necessary
when axle housing is replaced or pinion select
shim pack is unknown. It is also recommended
when ring and pinion gears are replaced.

PINION GEAR DEPTH VARIANCE

J FRONT SUSPENSION AND AXLE 2 - 39

Fig. 43 Master Bearing Tools On Hubs

Fig. 44 Differential Case End Play Measurement

Measurements are done with pinion cups and pin­ion bearings installed in housing. Take measure­ments with Pinion Gauge Set 6774, Pinion Block
6733 and Dial Indicator C-3339 (Fig. 45).

(1) Assemble Pinion Gauge Set, Pinion Block and
pinion bearings. Install assembly into differential
pinion gear bore and hand tighten cone (Fig. 46).

(2) Place Arbor Disc 6732 on Arbor D-115-3 and
position in the bearing cradles (Fig. 47). Install dif­ferential bearing caps on Arbor Discs and tighten
caps snug only.

Fig. 45 Pinion Gear Depth Gauge Tools

Fig. 46 Pinion Height Block

Fig. 47 Gauge Tools In Housing

2 - 40 FRONT SUSPENSION AND AXLE J

Arbor Discs have different steps to fit other
axle sizes. Pick correct size step for axle being
serviced.

(3) Firmly place Scooter Block and Dial Indicator
on pinion height block tool and zero the dial indica­tor pointer.

(4) Slide the Scooter Block across the arbor while
observing indicator (Fig. 48). Record the longest
travel distance, whether inward (-) or outward (+),
indicated by the pointer.

The plunger travel distance indicated, plus or
minus the variance etched in the gear is the re­quired thickness for the depth shims.

(5) Measure the thickness of each depth shim with
a micrometer and combine the shims necessary for

total required shim pack thickness. Include oil

slinger or baffle thickness with the total shim
pack thickness.

(6) Remove the measurement tools from the differ-

ential housing.

PINION GEAR ASSEMBLY/INSTALLATION

(1) Place the shims (and baffle if equipped) in the
pinion gear rear bearing bore. Install the bearing cup
with Installer D-146 and Driver Handle C-4171 (Fig.

49). Ensure cup is correctly seated.

(2) Install the pinion front bearing cup with In­staller D-144 and Handle C-4171 (Fig. 50).

Fig. 48 Pinion Depth Measurement

Fig. 50 Pinion Front Bearing Cup Installation

(3) Install the rear bearing and oil slinger on the
pinion gear with Installer W-262 until completely
seated (Fig. 51).

Fig. 49 Pinion Rear Bearing Cup Installation

Fig. 51 Pinion Rear Bearing Installation

J FRONT SUSPENSION AND AXLE 2 - 41

(4) Assemble collapsible spacer onto pinion shaft

(Fig. 52).

Fig. 52 Collapsible Preload Spacer

(5) Install pinion front bearing cone into cup and

end yoke thrust washer.

(6) Apply a light coat of gear lubricant on lip of
new pinion seal. Install seal with Installer W-147-E
and Handle C-4171 (Fig. 53).

(7) Install pinion gear into differential housing.

Fig. 54 Pinion Yoke Installation

(9) Install the yoke washer and a new nut on the
pinion gear. Use Flange Wrench C-3281 to retain the
yoke (Fig. 55). Tighten nut to 216 Nzm (160 ft.lbs.)
torque or enough to remove play. Do not over-
tighten.

Fig. 53 Pinion Seal Installation

(8) Install yoke with Installer W-162-D and

Wrench C-3281 (Fig. 54).

Fig. 55 Tightening Pinion Nut

CAUTION: Never loosen the pinion gear nut to de­crease the pinion gear bearing preload torque. If the
specified preload torque is exceeded, a new col­lapsible spacer must be installed. The torque se­quence will have to be repeated.

2 - 42 FRONT SUSPENSION AND AXLE J

(10) Use Flange Wrench C-3281 to retain the yoke
(Fig. 55). Slowly tighten the nut in small increments
until the rotating torque is achieved. Measure the ro­tating torque frequently to avoid over-tightening the
nut.

(11) Check bearing rotating torque with an inch
pound torque wrench (Fig. 56). The torque necessary
to rotate the pinion gear should be;

Fig. 56 Check Pinion Gear Torque

• Original Bearings — 1 to 3 Nzm (10 to 20 in. lbs.).

• New Bearings—2to5Nzm (15 to 35 in. lbs.).

DIFFERENTIAL SHIM PACK MEASUREMENT AND
ADJUSTMENT

(1) Place Master Differential Bearing D-134
(D-348) on the case hubs.

(2) Install a pilot stud at the left side of housing.
Attach Dial Indicator to housing. Load the indicator
plunger against the back of the ring gear (Fig. 57).
Ensure ring and pinion gear teeth are tightly
meshed. Zero the indicator.

(3) Insert a small pry bar between the bearing cap
and left side of differential case. Pry the case as far
as possible to right side (Fig. 57). Zero the dial indi­cator pointer.

(4) Repeat the measurement several times to check
consistency. Record the travel distance.

The measurement above shows shim thickness
necessary to eliminate ring gear backlash. Sub­tract this thickness from case zero end-play
shim thickness (Fig. 58). The shims must be
placed at the ring gear side between the case
and bearing.

(5) Remove indicator and pilot stud.

(6) Remove the differential case from housing.

Fig. 57 Shim Pack Measurement

Fig. 58 Shim Pack Calculations

(7) Remove the master bearing tools from the dif-

ferential case hubs.

(8) Position the backlash shims (with determined
thickness) on case hub (ring gear side). Install bear­ing on the hub with Bearing Installer C-3716-A and
Driver Handle C-4171 (Fig. 59).

(9) Position the remaining zero end-play shims on
hub at opposite side of case. Include an additional

J FRONT SUSPENSION AND AXLE 2 - 43

stud. Load the indicator plunger against the opposite
side of the housing (Fig. 60) and zero the indicator.

CAUTION: Do not spread over 0.38 mm (0.015 in). If
the housing is over-separated, it could be distorted
or damaged.

(3) Spread the housing enough to install the case
in the housing. Measure the distance with the dial
indicator (Fig. 60).

(4) Remove the dial indicator.

(5) Install case in the housing. Tap the differential
case to ensure the bearings are fully seated (Fig. 61).
Remove the spreader.

Fig. 59 Differential Bearing Installation

0.015 in. (0.38 mm) thick shim on this hub. This will
provide the required differential bearing preload
torque.

(10) Install bearings on hubs with Installer

C-3716-A and Handle C-4171 (Fig. 59).

(11) Match each bearing cup with bearing (origi-

nal). Install the cups on the bearings.

DIFFERENTIAL INSTALLATION

(1) Position Spreader W-129-B with the tool dowel
pins seated in the locating holes (Fig. 60). Install the
holddown clamps and tighten the tool turnbuckle fin­ger-tight.

Fig. 61 Differential Installation

(6) Install the bearing caps at their original loca­tions (Fig. 62). Tighten the bearing cap bolts to 61
Nzm (45 ft. lbs.) torque.

Fig. 60 Spread Differential Housing

(2) Install a pilot stud at the left side of the differ-

ential housing. Attach Dial Indicator to housing pilot

Fig. 62 Differential Bearing Cap Reference Letters

2 - 44 FRONT SUSPENSION AND AXLE J

BACKLASH AND CONTACT PATTERN ANALYSIS

(1) Rotate assembly several revolutions to seat
bearings. Measure backlash at three equally spaced
locations around the perimeter of the ring gear with
a dial indicator (Fig. 63).

Fig. 63 Ring Gear Backlash Measurement

The ring gear backlash must be within 0.005 -

0.008 inch (0.12 - 0.20 mm). It cannot vary more
than 0.002 inch (0.05 mm) between the points
checked.

If backlash must be adjusted, transfer shims from
one side of carrier to the other side. Adjust the back­lash accordingly (Fig. 64). DO NOT INCREASE

THE TOTAL SHIM PACK THICKNESS, EXCES­SIVE BEARING PRELOAD AND DAMAGE
WILL OCCUR.

If the mesh and backlash steps have been followed
in the procedures above, good gear teeth contact pat­terns should exist.

The ring gear teeth contact patterns will show if
the pinion gear depth is correct. It will also show if
the ring gear backlash has been adjusted correctly.
The backlash must be maintained within the speci­fied limits until the correct tooth contact patterns are
obtained.

(2) Apply a thin coat of hydrated ferric oxide (yel­low oxide of iron) to the drive and coast side of the
ring gear teeth.

(3) Rotate the ring gear one complete revolution in
both directions while a load is being applied. Insert a
pry bar between the differential housing and the case
flange. This action will produce distinct contact pat­terns on both the drive side and coast side of the ring
gear teeth.

(4) Note patterns in compound. Refer to (Fig. 65)
for interpretation of contact patterns and adjust ac­cordingly.

FINAL ASSEMBLY

(1) Install the axle shafts. Refer to Axle Shaft In­stallation in this Group.

(2) Scrape the residual sealant from the housing
and cover mating surfaces. Clean the mating sur­faces with mineral spirits. Apply a bead of MOPARt
Silicone Rubber Sealant on the housing cover (Fig.

66). Allow the sealant to cure for a few minutes.

Install the housing cover within 5 minutes af­ter applying the sealant. If not installed the seal­ant must be removed and another bead applied.

(3) Install the cover on the differential with the at­taching bolts. Install the identification tag. Tighten
the cover bolts with 41 Nzm (30 ft. lbs.) torque.

Fig. 64 Backlash Shim Adjustment

CAUTION: Overfilling the differential can result in
the lubricant foaming and overheating.

(4) Refill the differential housing with the speci­fied quantity of MOPARt Hypoid Gear Lubricant.

(5) Install the fill hole plug and tighten to 34 Nzm
(25 ft. lbs.) torque.

J FRONT SUSPENSION AND AXLE 2 - 45

Fig. 65 Gear Tooth Contact Patterns

2 - 46 FRONT SUSPENSION AND AXLE J

Fig. 66 Typical Housing Cover With Sealant

AXLE SPECIFICATIONS

MODEL 30 FRONT AXLE

J FRONT SUSPENSION AND AXLE 2 - 47

TORQUE SPECIFICATIONS

YJ FRONT SUSPENSION COMPONENTS

XJ FRONT SUSPENSION COMPONENTS

MODEL 30 AXLE

J FUEL SYSTEM 14 - 1

FUEL SYSTEM

CONTENTS

page page

ACCELERATOR PEDAL AND THROTTLE CABLE

... 16

FUEL DELIVERY SYSTEM ................. 2

FUEL TANKS ........................... 12

GENERAL INFORMATION .................. 1

MULTI-PORT FUEL INJECTION (MFI)—COMPO-

NENT DESCRIPTION/SYSTEM OPERATION . 17

GENERAL INFORMATION

Throughout this group, references are made to par­ticular vehicle models by alphabetical designation or
by the particular vehicle nameplate. A chart showing
a breakdown of the alphabetical designations is in­cluded in the Introduction section at the beginning of
this manual.

The Fuel System consists of: the fuel tank, an
electric (fuel tank mounted) fuel pump and a fuel fil­ter. It also consists of fuel tubes/lines/hoses, vacuum
hoses, throttle body and fuel injectors.

The Fuel Delivery System consists of: the electric
fuel pump, fuel filter, fuel tubes/lines/hoses, fuel rail,
fuel injectors and fuel pressure regulator.

A Fuel Return System is used on all vehicles.
The system consists of: the fuel tubes/lines/hoses that
route fuel back to the fuel tank.

The Fuel Tank Assembly consists of: the fuel
tank, filler tube, fuel gauge sending unit/electric fuel
pump module, a pressure relief/rollover valve and a
pressure-vacuum filler cap.

Also to be considered part of the fuel system is the
Evaporation Control System. This is designed to
reduce the emission of fuel vapors into the atmo­sphere. The description and function of the Evapora­tive Control System is found in Group 25, Emission
Control Systems.

MULTI-PORT FUEL INJECTION (MFI)—

COMPONENT REMOVAL/INSTALLATION ... 54

MULTI-PORT FUEL INJECTION (MFI)—

GENERAL DIAGNOSIS .................. 32

SPECIFICATIONS ....................... 62

age as a result of heavy knock operation may not be
covered by the new vehicle warranty.

In addition to using unleaded gasoline with the

proper octane rating, those that contain deter-

gents, corrosion and stability additives are rec­ommended. Using gasolines that have these

additives will help improve fuel economy, reduce
emissions and maintain vehicle performance. Gener­ally, premium unleaded gasolines contain more addi­tive than regular unleaded gasolines.

Poor quality gasoline can cause problems such
as hard starting, stalling and stumble. If you experi­ence these problems, use another brand of gasoline
before considering service for the vehicle.

GASOLINE/OXYGENATE BLENDS

Some fuel suppliers blend unleaded gasoline with
materials that contain oxygen such as alcohol, MTBE
and ETBE. The type and amount of oxygenate used
in the blend is important. The following are generally
used in gasoline blends:

ETHANOL

Ethanol (Ethyl or Grain Alcohol) properly blended,
is used as a mixture of 10 percent ethanol and 90
percent gasoline. Gasoline with ethanol may be

used in your vehicle.

FUEL USAGE STATEMENT

Your vehicle was designed to meet all emission reg­ulations and provide excellent fuel economy using
high quality unleaded gasoline. Only use unleaded
gasolines having a minimum posted octane of 87.

If your vehicle develops occasional light spark
knock (ping) at low engine speeds, this is not harm­ful. However, continued heavy knock at high

speeds can cause damage and should be re­ported to your dealer immediately. Engine dam-

METHANOL

CAUTION: DO NOT USE GASOLINES CONTAINING
METHANOL. Use of methanol/gasoline blends may re-

sult in starting and driveability problems. In addition,
damage may be done to critical fuel system compo­nents.

Methanol (Methyl or Wood Alcohol) is used in a va-

riety of concentrations blended with unleaded gaso-

14 - 2 FUEL SYSTEM J

line. You may encounter fuels containing 3 percent
or more methanol along with other alcohols called co­solvents.

Problems that are the result of using methanol/gas­oline blends are not the responsibility of Chrysler
Corporation. They may not be covered by the vehicle
warranty.

MTBE/ETBE

Gasoline and MTBE (Methyl Tertiary Butyl Ether)
blends are a mixture of unleaded gasoline and up to
15 percent MTBE. Gasoline and ETBE (Ethyl Ter­tiary Butyl Ether) are blends of gasoline and up to
17 percent ETBE. Gasoline blended with MTBE or
ETBE may be used in your vehicle.

FUEL DELIVERY SYSTEM

INDEX

page page

Fuel Filter ............................... 8

Fuel Pressure Leak Down Test ...............7

Fuel Pressure Release Procedure ............. 5

Fuel Pump Capacity Test ................... 7

Fuel Pump Electrical Control ................. 5

CLEAN AIR GASOLINE

Many gasolines are now being blended that con­tribute to cleaner air, especially in those areas of the
country where air pollution levels are high. These
new blends provide a cleaner burning fuel and some
are referred to as Reformulated Gasoline.

In areas of the country where carbon monoxide lev­els are high, gasolines are being treated with oxy­genated materials such as MTBE, ETBE and
ethanol.

Chrysler Corporation supports these efforts toward
cleaner air and recommends that you use these gas­olines as they become available.

Fuel Pump Module ........................ 2

Fuel System Pressure Test .................. 5

Fuel Tubes/Lines/Hoses and Clamps ........... 9

Quick-Connect Fittings ..................... 9

FUEL PUMP MODULE

The fuel pump module is installed in the top of the
fuel tank. The fuel pump module contains the follow­ing components:

• Electric fuel pump

• Fuel pump reservoir

• In-tank fuel filter

• Fuel gauge sending unit

• Fuel supply and return tube connections

The fuel pump used on all vehicles is a gear/rotor
type pump. It is driven by a permanent magnet 12
volt electric motor that is immersed in the fuel tank.
The electrical pump is integral with the fuel sender
unit. The pump/sender assembly is installed inside
the fuel tank.

The fuel pump has a check valve at the outlet end
that consists of a ball held against a seat by force ap­plied from a spring. When the pump is operating,
fuel pressure overcomes spring pressure and forces
the ball off its seat, allowing fuel to flow. When the
pump is not operating, spring pressure forces the ball
back against the seat preventing fuel backflow
through the pump.

Fuel system pressure is maintained at approxi­mately 214 kPa (31 psi). This is when the pump is
operating and vacuum is supplied to the fuel pres­sure regulator. If vacuum is not supplied to the pres­sure regulator, fuel pressure will be approximately
55-69 kPa (8-10 psi) higher. This may be due to a
broken or clogged vacuum line. When the fuel pump

is not operating, system fuel pressure of 131-269 kPa
(19-39 psi) is maintained. This is done by the fuel
pump outlet check valve and the vacuum assisted
fuel pressure regulator.

REMOVAL—XJ MODELS

The fuel pump/gauge sender unit assembly can be
removed from the fuel tank without removing the
tank from the vehicle.

WARNING: THE FUEL SYSTEM IS UNDER A CON­STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING THE FUEL PUMP MODULE,
THE FUEL SYSTEM PRESSURE MUST BE RE­LEASED. REFER TO THE FUEL PRESSURE RE­LEASE PROCEDURE IN THIS GROUP.

WARNING: EXTINGUISH ALL TOBACCO SMOKING
PRODUCTS BEFORE SERVICING THE FUEL SYS­TEM. KEEP OPEN FLAME AWAY FROM FUEL SYS­TEM COMPONENTS.

(1) Remove fuel filler cap. Perform the Fuel Pres­sure Release Procedure as outlined in this group.

(2) Disconnect negative battery cable.

(3) Using an approved portable gasoline siphon/
storage tank, drain fuel tank until fuel level is below
one quarter (1/4) full.

(4) Raise and support vehicle.

J FUEL SYSTEM 14 - 3

WARNING: WRAP SHOP TOWELS AROUND FUEL
HOSES TO ABSORB ANY FUEL SPILLAGE DURING
FUEL TANK REMOVAL.

(5) Disconnect fuel vent supply and return tubes

from fittings on fuel pump module.

(6) Disconnect fuel pump module electrical harness

connector from main harness.

(7) Using a brass punch and hammer, remove fuel
pump module lock ring by carefully tapping it coun­terclockwise (Fig. 1).

Fig. 2 Fuel Pump Module—XJ

Models—Disassemble/Assemble

INSTALLATION—XJ MODELS

Whenever the fuel pump is replaced, the fuel

pump inlet filter must also be replaced.

(1) Install new fuel pump inlet filter onto fuel

Fig. 1 Removing Lock Ring—XJ Models—Typical

(8) Remove fuel pump module and O-ring seal.
Discard old O-ring and fuel pump module inlet filter.

DISASSEMBLY—XJ MODELS

(1) Remove and discard fuel pump inlet filter.

The wire terminals to the fuel pump motor are dif­ferent in size and cannot be connected to the wrong
terminal.

(2) Disconnect fuel pump terminal wires.

(3) Remove fuel pump outlet hose and clamp. Re­place the hose if it shows any signs of fatigue or fail­ure.

(4) Remove fuel pump top mounting bracket nut.
Remove fuel pump (Fig. 2).

pump.

(2) Install fuel pump module assembly and new O­ring seal. The rubber stopper on the end of the fuel
return tube of the assembly must be inserted into the
cup in the fuel tank reservoir (Fig. 3).

ASSEMBLY—XJ MODELS

Whenever the fuel pump is replaced, the fuel pump

inlet filter (sock) must also be replaced.

(1) Place fuel pump top mounting bracket over top

of pump.

(2) Position fuel pump into lower bracket. Slide
stud of top bracket through hole in fuel pump side
bracket. Tighten fuel pump top mounting nut.

(3) Install new fuel pump outlet hose. Secure with
new clamps.

(4) Connect wire terminals to motor.

(5) Install new fuel pump inlet filter.

Fig. 3 Fuel Pump Module—XJ Models—Installation

14 - 4 FUEL SYSTEM J

(3) Using a brass punch and a hammer, install
lock ring. Carefully tap lock ring clockwise until it
seats against stop on fuel tank.

(4) Connect fuel supply and return hoses to fittings
on fuel pump module. Tighten hose clamps.

(5) Connect fuel pump module electrical harness
connector to main harness connector.

(6) Lower vehicle.

(7) Fill fuel tank. Install fuel tank cap.

(8) Connect negative battery cable.

(9) Start vehicle and inspect for leaks.

REMOVAL—YJ MODELS

The fuel tank must be removed to remove the fuel
pump module.

WARNING: THE FUEL SYSTEM IS UNDER A CON­STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING THE FUEL PUMP MODULE,
THE FUEL SYSTEM PRESSURE MUST BE RE­LEASED. REFER TO THE FUEL PRESSURE RE­LEASE PROCEDURE IN THIS GROUP.

WARNING: EXTINGUISH ALL TOBACCO SMOKING
PRODUCTS BEFORE SERVICING THE FUEL SYS­TEM. KEEP OPEN FLAME AWAY FROM FUEL SYS­TEM COMPONENTS.

(1) Remove negative battery cable.

(2) Remove fuel filler cap. Perform the Fuel Pres­sure Release Procedure as outlined in this group.

(3) Remove fuel tank. Refer to Fuel Tank Remov­al—YJ Models.

(4) Remove fuel pump module assembly.

(5) Remove mounting screws. Lift assembly and
gasket out of fuel tank. Discard old gasket (Fig. 4).

DISASSEMBLY—YJ MODELS

(1) Remove and discard fuel pump inlet filter (Fig.

5).

Fig. 5 Fuel Pump Module—YJ Models

The wire terminals to the fuel pump motor are dif­ferent in size and cannot be connected to the wrong
terminal.

(2) Disconnect fuel pump terminal wires from
pump.

(3) Remove fuel pump outlet hose and clamp (Fig.

6). Replace the hose if it shows any signs of fatigue
or failure.

(4) Remove fuel pump top mounting bracket nut
(Fig. 6). Remove fuel pump.

Fig. 4 Fuel Pump Module—Remove/Install—YJ

Models

(6) Remove and discard fuel pump inlet filter.

Fig. 6 Fuel Pump Removal/Installation—YJ Models

ASSEMBLY—YJ MODELS

Whenever the fuel pump is replaced, the fuel pump
inlet filter (sock) must also be replaced.

(1) Place fuel pump top mounting bracket over top
of pump.

(2) Position fuel pump into lower bracket. Slide
stud of top bracket through hole in fuel pump side
bracket. Tighten fuel pump top mounting nut.

J FUEL SYSTEM 14 - 5

(3) Install new fuel pump outlet hose. Secure with

new clamps.

(4) Connect wire terminals to motor.
(5) Install new fuel pump inlet filter.

INSTALLATION—YJ MODELS

(1) Install a new fuel pump inlet filter.

(2) Install fuel pump module assembly with a new
gasket between the assembly and tank. Tighten
mounting screws to 2 Nzm (18 in. lbs.) torque.

(3) Install fuel tank. Refer to Fuel Tank Installa­tion—YJ Models.

(4) Fill fuel tank. Install fuel tank cap.

(5) Install negative battery cable.

(6) Start vehicle and check for leaks.

FUEL PUMP ELECTRICAL CONTROL

For an electrical operational description of the fuel
pump, refer to the MFI System—Component Descrip­tion/System Operation section of this group. See Au­tomatic Shut Down (ASD) Relay—PCM Output.

For the 1994 model year, the ballast resistor and
ballast resistor bypass relay are no longer used to
control the fuel pump circuit.

FUEL PRESSURE RELEASE PROCEDURE

WARNING: THE FUEL SYSTEM IS UNDER CON­STANT FUEL PRESSURE (EVEN WITH THE ENGINE
OFF) OF APPROXIMATELY 131-269 KPA (19-39
PSI). THIS PRESSURE MUST BE RELEASED BE­FORE SERVICING ANY FUEL SUPPLY OR FUEL RE­TURN SYSTEM COMPONENT.

(1) Disconnect negative battery cable.

(2) Remove fuel tank filler neck cap to release fuel
tank pressure.

WARNING: DO NOT ALLOW FUEL TO SPILL ONTO
THE ENGINE INTAKE OR EXHAUST MANIFOLDS.
PLACE SHOP TOWELS UNDER AND AROUND THE
PRESSURE PORT TO ABSORB FUEL WHEN THE
PRESSURE IS RELEASED FROM THE FUEL RAIL.

Fig. 7 Pressure Test Port—Typical

(8) After fuel pressure has been released, remove

the hose from the test port.

(9) Install protective cap to fuel test port.

FUEL SYSTEM PRESSURE TEST

The fuel system is equipped with a vacuum as­sisted fuel pressure regulator (Fig. 8). With engine at
idle speed, system fuel pressure should be approxi­mately 214 kPa (31 psi) with the vacuum line con­nected to the regulator. With the vacuum line
disconnected from the regulator, fuel pressure should
be approximately 269 kPa (39 psi). This is 55-69 kPa
(8-10 psi) higher.

(1) Remove the protective cap at the fuel rail (Fig.

7). Connect the 0-414 kPa (0-60 psi) fuel pressure
gauge (from Gauge Set 5069) to test port pressure fit­ting on fuel rail (Fig. 9).

WARNING: WEAR PROPER EYE PROTECTION
WHEN RELEASING FUEL SYSTEM PRESSURE.

(3) Remove protective cap from pressure test port

on the fuel rail (Fig. 7).

(4) Obtain the fuel pressure gauge/hose assembly
from fuel pressure gauge tool set 5069. Remove the
gauge from the hose.

(5) Place one end of hose (gauge end) into an ap­proved gasoline container.

(6) Place a shop towel under the test port.

(7) To release fuel pressure, screw the other end of
hose onto the fuel pressure test port.

Fig. 8 Fuel Pressure Regulator—Typical

(2) Note pressure gauge reading. Fuel pressure

should be approximately 214 kPa (31 psi) at idle.

14 - 6 FUEL SYSTEM J

Fig. 9 Fuel Pressure Test Connection—Typical

(3) Disconnect vacuum line (hose) at fuel pressure
regulator (Fig. 8). Note gauge reading. With vacuum
line disconnected, fuel pressure should rise to approx­imately 269 kPa (39 psi).

Fuel pressure should be approximately 55-69 kPa
(8-10 psi) higher with vacuum line removed from
regulator. If not, inspect pressure regulator vacuum
line for leaks, kinks or blockage. If vacuum line
checks OK and fuel pressure does not rise approxi­mately 8-10 psi after disconnecting vacuum line, re­place fuel pressure regulator.

The fuel pressure regulator is not adjustable.

(4) If fuel pressure exceeds 45 psi, check fuel re­turn line/tube for kinks or obstructions.

If the previous tests checked good, fuel pump pres­sure is correct. If pump pressure was low, proceed as
follows:

(5) Release fuel system pressure. Refer to the pre­vious Fuel Pressure Release Procedure in this group.

(6) Disconnect the 5/16 inch fuel return line quick­connect fitting at fuel rail. For procedures, refer to
Fuel Tubes/Lines/Hoses and Clamps. Also refer to
Quick-Connect Fittings. These can be found in the
Fuel Delivery System section of this group.

Connect Fuel Line Pressure Test Adapter Tool
number 6539 (5/16 in.) between the disconnected fuel
return line and fuel rail (Fig. 10).

WARNING: THE FUEL SYSTEM PRESSURE IN THE
FOLLOWING TEST MAY EXCEED 100 PSI. BEFORE
STARTING TEST, VERIFY GOOD CONNECTIONS AT
ENDS OF ADAPTER TOOL 6539. BE SURE TOOL IS
LOCKED ONTO FUEL RAIL AND FUEL RETURN
LINE. PULL FIRMLY ON ENDS OF TOOL TO VER­IFY.

(7) To activate the fuel pump and pressurize the
system, obtain the DRB scan tool. Refer to the appro­priate Powertrain Diagnostic Procedures service
manual for DRB operation.

Fig. 10 Adapter Tool—Typical Connection

(8) MOMENTARILY pinch the rubber hose por­tion of adapter tool 6539. Pressure should rise to ap­proximately 75 psi within two (2) seconds. DO NOT
pinch hose for longer than three seconds.

If fuel pump pressure rises to approximately 75 psi
within two seconds, pressure is operating at its max­imum and is correct.

If fuel pump pressure does not rise to approxi­mately 75 psi within two seconds, proceed as follows:

(9) Release fuel system pressure. Refer to the pre­vious Fuel Pressure Release Procedure in this group.

(10) Raise and support vehicle.

(11) Disconnect fuel supply line at inlet (fuel tank
side) of fuel filter. Connect Fuel Line Pressure Test
Adapter Tool number 6631 (3/8 in.) between fuel fil­ter and fuel supply line.

WARNING: THE FUEL SYSTEM PRESSURE IN THE
FOLLOWING TEST MAY EXCEED 100 PSI. BEFORE
STARTING TEST, VERIFY GOOD CONNECTIONS AT
ENDS OF ADAPTER TOOL 6631. BE SURE TOOL IS
LOCKED ONTO FUEL FILTER AND FUEL SUPPLY
LINE. PULL FIRMLY ON ENDS OF TOOL TO VER­IFY.

(12) To activate the fuel pump and pressurize the
system, obtain the DRB scan tool. Refer to the appro­priate Powertrain Diagnostic Procedures service
manual for DRB operation.

MOMENTARILY pinch the rubber hose portion of
adapter tool 6631. Pressure should rise to approxi­mately 75 psi within two (2) seconds. DO NOT pinch
hose for longer than three seconds.

If fuel pump pressure now rises to approximately
75 psi within two seconds, but this pressure could not
be met at the fuel rail, check for a plugged or re­stricted fuel filter. Also check the fuel supply line be­tween fuel filter and fuel rail for kinks or
obstructions. Proceed to the following Fuel Pump Ca­pacity Test.

J FUEL SYSTEM 14 - 7

FUEL PUMP CAPACITY TEST

Before performing this test, verify fuel pump pres-

sure by performing the previous tests.

(1) Release the fuel system pressure from fuel sys­tem. Refer to the previous Fuel Pressure Release
Procedure in this group.

(2) Disconnect the fuel supply line at fuel rail near
pressure regulator. For procedures, refer to Fuel
Tubes/Lines/Hoses and Clamps. Also refer to Quick­Connect Fittings. These can be found in the Fuel De­livery System section of this group.

(3) Connect Fuel Line Pressure Test Adapter Tool
number 6631 (3/8 in.) into the disconnected fuel sup­ply line. Insert the other end of tool 6631 into an ap­proved gasoline container.

(4) To activate the fuel pump and pressurize the
system, obtain the DRB scan tool. Refer to the appro­priate Powertrain Diagnostic Procedures service
manual for DRB operation.

A good fuel pump will deliver at least 1 liter of fuel
per minute.

FUEL PRESSURE LEAK DOWN TEST

ENGINE OFF

Abnormally long periods of cranking to restart a
hot engine that has been shut down for a short pe­riod of time may be caused by:

• Fuel pressure bleeding past the fuel pressure reg­ulator.

• Fuel pressure bleeding past the check valve in the
outlet end of the fuel tank mounted fuel pump.

(1) Remove protective cap at fuel rail test port
(Fig. 11). With the engine off, connect an accurate
0-689 kPa (0-100 psi) fuel gauge to the pressure test
port fitting on the fuel rail. The fitting on the pres­sure tester must be in good condition and free of any
leaks before performing this test.

(2) Start the vehicle and let engine idle. Check
fuel pressure reading on gauge. Fuel pressure should
be within specifications. Refer to the previous Fuel
System Pressure Tests.

(3) Shut engine off. Observe and record fuel pres­sure reading on gauge. Leave fuel pressure gauge
connected. Allow engine to set for 30 minutes and
then compare the fuel pressure reading on the gauge
with the reading taken when engine was shut down.
A pressure drop of up to 138 kPa (20 psi) within 30
minutes is within specifications.

(4) If the fuel pressure drop is within specifica­tions, the fuel pump outlet check valve and fuel pres­sure regulator are both operating normally.

(5) If fuel pressure drop is greater than 138 kPa
(20 psi), it must be determined if this drop is being
caused by (in-tank mounted) fuel pump outlet check
valve or fuel pressure regulator. Proceed to next step.

(6) Release the fuel system pressure from fuel sys­tem. Refer to the previous Fuel Pressure Release
Procedure in this group.

(7) Disconnect both fuel lines at fuel rail near fuel
pressure regulator. For procedures, refer to Fuel
Tubes/Lines/Hoses and Clamps. Also refer to Quick­Connect Fittings. These can be found in the Fuel De­livery System section of this group.

(8) Connect Fuel Line Pressure Test Adapter Tool
number 6631 (3/8 in.) between the disconnected fuel
supply line and fuel rail (Fig. 12).

(9) Connect Fuel Line Pressure Test Adapter Tool
number 6539 (5/16 in.) between the disconnected fuel
return line and fuel rail (Fig. 12).

Fig. 11 Fuel Pressure Test Port—Typical

Fig. 12 Adapter Tools—Typical Connections

(10) Start engine. Observe and record fuel system
pressure.

(11) Shut engine off.

(12) Clamp off the rubber hose portion of adapter
tool number 6539 connected to the fuel return line.
Allow engine to set for 30 minutes. If pressure has
dropped more than 138 kPa (20 psi) in 30 minutes,

14 - 8 FUEL SYSTEM J

pressure is bleeding past the (in-tank mounted) fuel
pump outlet check valve. Replace Fuel Pump Module
assembly. Refer to Fuel Pump Module removal and
installation in this group. If pressure drop is within
specifications, proceed to next step.

(13) Clamp off the rubber hose portion of adapter
tool number 6631 connected to the fuel supply line.
Allow engine to set for 30 minutes. If pressure has
dropped more than 138 kPa (20 psi) in 30 minutes,
pressure is bleeding past the fuel pressure regulator.
Replace fuel pressure regulator. Refer to Fuel Rail
removal and installation in the Component Removal/
Installation section of this group.

MECHANICAL MALFUNCTIONS

Mechanical malfunctions are more difficult to diag­nose with this system. The powertrain control mod­ule (PCM) has been programmed to compensate for
some mechanical malfunctions such as incorrect cam
timing, vacuum leaks, etc. If engine performance
problems are encountered and diagnostic trouble
codes are not displayed, the problem may be mechan­ical rather than electronic.

REMOVAL

Fig. 14 Fuel Filter—XJ Models

FUEL FILTER

The fuel filter protects the fuel injectors and fuel
pressure regulator from dirt, water and other foreign
matter. The filter is located under the vehicle along
the frame rail (Figs. 13 or 14). Replace fuel filter at
intervals specified in the Lubrication and Mainte­nance Schedule chart found in Group 0, Lubrication
and Maintenance.

WARNING: THE FUEL SYSTEM IS UNDER CON­STANT FUEL PRESSURE (EVEN WITH THE ENGINE
OFF) OF APPROXIMATELY 131-269 KPA (19-39
PSI). THIS PRESSURE MUST BE RELEASED BE­FORE SERVICING THE FUEL FILTER.

(1) Disconnect negative battery cable. Remove fuel

filler cap.

WARNING: FUEL PRESSURE MUST BE RELEASED
BEFORE DISCONNECTING ANY FUEL SYSTEM
COMPONENT.

(2) Release fuel system pressure. Refer to Fuel

Pressure Release Procedure in this group.

(3) Raise and support vehicle.
(4) On YJ models remove the fuel filter shield

(Fig. 13).

(5) Remove hoses and clamps from inlet and outlet
sides of filter (Figs. 13 or 14). For procedures, refer to
Fuel Tubes/Lines/Hoses and Clamps. Also refer to
Quick-Connect Fittings. These can be found in the
Fuel Delivery System section of this group.

(6) Remove retaining strap bolt.

(7) Remove filter from vehicle.

Fig. 13 Fuel Filter and Shield—YJ Models

INSTALLATION

CAUTION: The ends of the fuel filter are marked for
correct installation. Install filter with the end marked
IN towards fuel tank and the end marked OUT to­wards engine.

J FUEL SYSTEM 14 - 9

(1) Place fuel filter in retaining strap with the

marked ends in the correct position.

(2) Install retaining strap bolt and tighten to 12

Nzm (106 in. lbs.) torque.

(3) Install inlet and outlet hoses and hose clamps.
For procedures, refer to Fuel Tubes/Lines/Hoses and
Clamps. Also refer to Quick-Connect Fittings. These
can be found in the Fuel Delivery System section of
this group.

(4) On YJ models, install fuel filter shield (Fig. 13).

(5) Lower vehicle.

(6) Connect negative battery cable.

(7) Start engine and check for leaks.

FUEL TUBES/LINES/HOSES AND CLAMPS

Also refer to the proceeding section on Quick-Con­nect Fittings.

WARNING: THE FUEL SYSTEM IS UNDER A CON­STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSES,
FITTINGS OR LINES, THE FUEL SYSTEM PRES­SURE MUST BE RELEASED. REFER TO THE FUEL
PRESSURE RELEASE PROCEDURE IN THIS
GROUP.

Different types of quick-connect fittings are used to
attach various fuel system components. These are: a
single-tab type, a two-tab type or a plastic retainer
ring type.

SINGLE-TAB TYPE

This type of fitting is equipped with a single pull
tab (Fig. 15). The tab is removable. After the tab is
removed, the quick-connect fitting can be separated
from the fuel system component.

Inspect all hose connections such as clamps, cou­plings and fittings to make sure they are secure and
leaks are not present. The component should be re­placed immediately if there is any evidence of degra­dation that could result in failure.

Never attempt to repair a plastic fuel line/tube. Re­place as necessary.

Avoid contact of any fuel tubes/hoses with other ve­hicle components that could cause abrasions or scuff­ing. Be sure that the plastic fuel lines/tubes are
properly routed to prevent pinching and to avoid heat
sources.

The lines/tubes/hoses used on fuel injected vehicles
are of a special construction. This is due to the
higher fuel pressures and the possibility of contami­nated fuel in this system. If it is necessary to replace
these lines/tubes/hoses, only those marked EFM/EFI
may be used.

The hose clamps used to secure rubber hoses on
fuel injected vehicles are of a special rolled edge con­struction. This construction is used to prevent the
edge of the clamp from cutting into the hose. Only
these rolled edge type clamps may be used in this
system. All other types of clamps may cut into the
hoses and cause high pressure fuel leaks.

Use new original equipment type hose clamps.
Tighten hose clamps to 1 Nzm (15 in. lbs.) torque.

Fig. 15 Single-Tab Type Fitting

CAUTION: The interior components (O-rings, spac­ers) of this type of quick-connect fitting are not ser­viced separately, but new pull tabs are available. Do
not attempt to repair damaged fittings or fuel lines/
tubes. If repair is necessary, replace the complete
fuel tube/quick-connect fitting assembly.

WARNING: THE FUEL SYSTEM IS UNDER A CON­STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSES,
FITTINGS OR LINES, THE FUEL SYSTEM PRES­SURE MUST BE RELEASED. REFER TO THE FUEL
PRESSURE RELEASE PROCEDURE IN THIS
GROUP.

DISCONNECTION/CONNECTION

(1) Disconnect negative battery cable from battery.

(2) Perform the fuel pressure release procedure.
Refer to the Fuel Pressure Release Procedure in this
section.

(3) Clean the fitting of any foreign material before
disassembly.

(4) Press the release tab on the side of fitting to re­lease pull tab (Fig. 15).

QUICK-CONNECT FITTINGS

Also refer to the previous Fuel Tubes/Lines/Hoses

and Clamps section.

14 - 10 FUEL SYSTEM J

CAUTION: If this release tab is not pressed prior to
releasing the pull tab, the pull tab will be damaged.

(5) While pressing the release tab on the side of
the fitting, use a screwdriver to pry up the pull tab
(Fig. 16).

Fig. 16 Disconnecting Single-Tab Type Fitting

(6) Raise the pull tab until it separates from the
quick-connect fitting (Fig. 17). Discard the old pull
tab.

(12) Verify a locked condition by firmly pulling on

fuel tube and fitting (15-30 lbs.).

(13) Connect negative cable to battery.
(14) Start engine and check for leaks.

TWO-TAB TYPE FITTING

This type of fitting is equipped with tabs located on
both sides of the fitting (Fig. 18). These tabs are sup­plied for disconnecting the quick-connect fitting from
component being serviced.

Fig. 17 Removing Pull Tab

(7) Disconnect the quick-connect fitting from the

fuel system component being serviced.

(8) Inspect the quick-connect fitting body and fuel

system component for damage. Replace as necessary.

(9) Prior to connecting the quick-connect fitting to
component being serviced, check condition of fitting
and component. Clean the parts with a lint-free
cloth. Lubricate them with clean engine oil.

(10) Insert the quick-connect fitting into the fuel
tube or fuel system component until the built-on stop
on the fuel tube or component rests against back of
fitting.

(11) Obtain a new pull tab. Push the new tab down
until it locks into place in the quick-connect fitting.

Fig. 18 Typical Two-Tab Type Quick-Connect Fitting

CAUTION: The interior components (O-rings, spac­ers) of this type of quick-connect fitting are not ser­viced separately, but new plastic retainers are
available. Do not attempt to repair damaged fittings
or fuel lines/tubes. If repair is necessary, replace
the complete fuel tube/quick-connect fitting assem­bly.

WARNING: THE FUEL SYSTEM IS UNDER A CON­STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSES,
FITTINGS OR LINES, THE FUEL SYSTEM PRES­SURE MUST BE RELEASED. REFER TO THE FUEL
PRESSURE RELEASE PROCEDURE IN THIS
GROUP.

DISCONNECTION/CONNECTION

(1) Disconnect negative battery cable from the bat-

tery.

(2) Perform the fuel pressure release procedure.
Refer to the Fuel Pressure Release Procedure in this
section.

(3) Clean the fitting of any foreign material before
disassembly.

(4) To disconnect the quick-connect fitting, squeeze
the plastic retainer tabs against the sides of the
quick-connect fitting with your fingers. Tool use is
not required for removal and may damage plastic re-

J FUEL SYSTEM 14 - 11

tainer. Pull the fitting from the fuel system compo­nent being serviced. The plastic retainer will remain
on the component being serviced after fitting is dis­connected. The O-rings and spacer will remain in the
quick-connect fitting connector body.

(5) Inspect the quick-connect fitting body and com-

ponent for damage. Replace as necessary.

CAUTION: When the quick-connect fitting was dis­connected, the plastic retainer will remain on the
component being serviced. If this retainer must be
removed, very carefully release the retainer from
the component with two small screwdrivers. After
removal, inspect the retainer for cracks or any dam­age.

(6) Prior to connecting the quick-connect fitting to
component being serviced, check condition of fitting
and component. Clean the parts with a lint-free
cloth. Lubricate them with clean engine oil.

(7) Insert the quick-connect fitting to the compo­nent being serviced and into the plastic retainer.
When a connection is made, a click will be heard.

(8) Verify a locked condition by firmly pulling on
fuel tube and fitting (15-30 lbs.).

(9) Connect negative cable to battery.

(10) Start engine and check for leaks.

PLASTIC RETAINER RING TYPE FITTING

This type of fitting can be identified by the use of a
full-round plastic retainer ring (Fig. 19) usually
black in color.

CAUTION: The interior components (O-rings, spac­ers, retainers) of this type of quick-connect fitting
are not serviced separately. Do not attempt to re­pair damaged fittings or fuel lines/tubes. If repair is
necessary, replace the complete fuel tube/quick­connect fitting assembly.

WARNING: THE FUEL SYSTEM IS UNDER A CON­STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSES,
FITTINGS OR LINES, THE FUEL SYSTEM PRES­SURE MUST BE RELEASED. REFER TO THE FUEL
PRESSURE RELEASE PROCEDURE IN THIS
GROUP.

DISCONNECTION/CONNECTION

(1) Disconnect negative battery cable from the bat­tery.

(2) Perform the fuel pressure release procedure.

Fig. 19 Plastic Retainer Ring Type Fitting

Refer to the Fuel Pressure Release Procedure in this
section.

(3) Clean the fitting of any foreign material before

disassembly.

(4) To release the fuel system component from the
quick-connect fitting, firmly push the fitting towards
the component being serviced while firmly pushing
the plastic retainer ring into the fitting (Fig. 19).
With the plastic ring depressed, pull the fitting from
the component. The plastic retainer ring must be

pressed squarely into the fitting body. If this re­tainer is cocked during removal, it may be dif­ficult to disconnect fitting. Use an open-end
wrench on the shoulder of the plastic retainer
ring to aid in disconnection.

After disconnection, the plastic retainer ring will
remain with the quick-connect fitting connector body.

(5) Inspect fitting connector body, plastic retainer
ring and fuel system component for damage. Replace
as necessary.

(6) Prior to connecting the quick-connect fitting to
component being serviced, check condition of fitting
and component. Clean the parts with a lint-free
cloth. Lubricate them with clean engine oil.

(7) Insert the quick-connect fitting into the compo­nent being serviced until a click is felt.

(8) Verify a locked condition by firmly pulling on
fuel tube and fitting (15-30 lbs.).

(9) Connect negative battery cable to battery.

(10) Start engine and check for leaks.

14 - 12 FUEL SYSTEM J

FUEL TANKS

INDEX

page page

Fuel Gauge Sending Unit ..................15

Fuel Tank ..............................12

Fuel Tank Filler Tube Cap .................12

Fuel Tank Pressure Relief/Rollover Valve ...... 15

GENERAL INFORMATION

All vehicles pass a full 360 degree rollover test
without fuel leakage. To accomplish this, fuel and
vapor flow controls are required for all fuel tank con­nections.

All models are equipped with a pressure relief/roll­over valve mounted in the top of the fuel pump mod­ule. The return line from the fuel pump to the fuel
tank contains a one-way check valve.

An evaporative control system prevents raw fuel
vapor from escaping into the atmosphere. Fuel va­pors from the fuel tank are collected in the EVAP
canister. When the engine is operating, the vapors
are drawn into the intake manifold to be used in
combustion. Refer to Group 25, Emission Control
System for more information.

Inspect all hose/tube connections for completeness.
Be sure that leaks are not present. Replace any hose
that is cracked, scuffed, swelled, has rubbed against
other vehicle components or shows any other sign of
wear that could lead to failure. If it is necessary to
replace a hose, only hose marked EFM/EFI may be
used.

When installing hoses, be sure that they are routed
away from contact with other vehicle components.

The hose clamps used on fuel injected vehicles are
of a special rolled edge construction to prevent the
edge of the clamp from cutting into the hose. Only
these rolled edge type clamps may be used on this
system. Other types of clamps may cut into the hoses
and cause high pressure fuel leaks.

FUEL TANK CAPACITIES

General Information ....................... 12

Heat Shields ............................12

No-Lead Fuel Tank Filler Tube .............. 12

NO-LEAD FUEL TANK FILLER TUBE

All vehicles are designed to operate using Un­leaded fuels. The diameter of the opening in the fuel
tank filler neck is sized to only accept unleaded fuel
nozzles. Gasoline station pumps for unleaded and
leaded fuels have different size nozzles. Leaded fuel
nozzles are larger in diameter than unleaded nozzles.
The fuel tank filler neck opening is also equipped
with a deflector, which the smaller unleaded nozzle
pushes back upon entering the filler neck. The de­flector will prevent the larger diameter leaded fuel
nozzles from entering the filler neck and will deflect
fuel away from the filler neck. This happens if filling
of the tank with leaded fuel is attempted.

A label is attached to the instrument panel under
the fuel gauge that reads UNLEADED FUEL ONLY
as a reminder to the driver. A similar label is located
near the fuel tank filler.

FUEL TANK FILLER TUBE CAP

The loss of any fuel or vapor out of the filler neck
is prevented by the use of a safety filler cap. This
will release only under pressure of 10.9 to 13.45 kPa
(1.58 to 1.95 psi). The vacuum release is between .97
and 2.0 kPa (.14 and .29 psi). This cap must be re­placed by a similar unit if replacement is necessary.

CAUTION: Remove the fuel tank filler tube cap prior
to removing or repairing fuel lines to relieve fuel
tank pressure.

HEAT SHIELDS

The sheet metal heat shields may have to be re­moved when servicing the fuel tank, fuel lines or va­por vent line. The heat shields must be installed to
protect the lines and tank from the heat of the ex­haust system. Refer to Group 11, Exhaust System
and Intake Manifold for proper installation.

FUEL TANK

WARNING: THE FUEL SYSTEM IS UNDER CON­STANT FUEL PRESSURE (EVEN WITH THE ENGINE
OFF) OF APPROXIMATELY 131-269 KPA (19-39
PSI). THIS PRESSURE MUST BE RELEASED BE­FORE SERVICING FUEL TANK.

J FUEL SYSTEM 14 - 13

REMOVAL—XJ MODELS

Perform the preceding Fuel System Pressure Re-

lease Procedure.

(1) Disconnect negative battery cable.

(2) Remove the fuel filler cap. Using an approved
portable gasoline siphon/storage tank, drain fuel
tank.

(3) Raise and support vehicle.

(4) Disconnect fuel fill hose and fill vent hose from
filler neck (Fig. 1).

Fig. 2 Skid Plate—XJ Models

Fig. 1 Filler Neck Hoses—XJ Models

(5) Disconnect fuel pump module wire connector.
Remove tie straps securing connector harness to fuel
supply and return tubes.

WARNING: WRAP SHOP TOWELS AROUND FUEL
HOSES TO ABSORB ANY FUEL SPILLAGE DURING
FUEL TANK REMOVAL.

(6) Disconnect fuel tank vent hose from vent tube.

(7) Disconnect fuel supply and return hoses from
tubes.

(8) If equipped, remove skid plate (Fig. 2).

(9) Remove fuel tank shield (Fig. 3).

(10) Center a transmission jack under the fuel tank.

(11) Remove support strap nuts. Move straps away
from tank (Fig. 3).

(12) Lower fuel tank on transmission jack.

INSTALLATION—XJ MODELS

(1) Raise fuel tank into position. Connect fuel fill
hose and vent hose to filler neck and tighten clamps.

(2) Wrap support straps around tank and over studs.
Tighten strap nuts to 11.3 Nzm (100 in. lbs.) torque.

(3) Remove transmission jack.

Fig. 3 Fuel Tank Remove/Install—XJ Models

(4) Install tank shield.
(5) If equipped, install tank skid plate.
(6) Connect vent hose to vent tube.
(7) Connect fuel supply hose to supply tube and

fuel return hose to return tube. Tighten hose clamps.

(8) Connect fuel pump module wire connector to
harness connector. Secure fuel pump module wire
harness to fuel tubes with tie straps.

(9) Lower vehicle.

(10) Fill fuel tank. Install filler cap.

(11) Connect negative battery cable to battery.

(12) Start vehicle and inspect for leaks.

14 - 14 FUEL SYSTEM J

REMOVAL—YJ MODELS

WARNING: EXTINGUISH ALL TOBACCO SMOKING
PRODUCTS BEFORE SERVICING THE FUEL SYS­TEM. KEEP OPEN FLAME AWAY FROM FUEL SYS­TEM COMPONENTS.

(1) Disconnect negative battery cable.
(2) Remove the fuel filler cap. Using an approved por-

table gasoline siphon/storage tank, drain fuel tank.

(3) Raise and support vehicle.

(4) Using a small straight blade screwdriver, pull
back the stems of the push clips that secure the fuel
filler neck shroud (located at bottom of left rear
wheel well) in place (Fig. 4). This unlocks the push
clip allowing them to be removed by pulling assem­bly out of shroud. Remove shroud.

(6) Disconnect fuel tank vent hose from vent tube.
Disconnect fuel supply and return hoses from tubes
(Fig. 6).

Fig. 6 Fuel Tank Hoses—YJ Models

The fuel tank and skid plate are removed as an as­sembly.

(7) Centrally position a transmission jack under
skid plate/fuel tank assembly.

(8) Remove skid plate/fuel tank assembly mount­ing nuts (Fig. 7). Do not loosen tank strap nuts.

Fig. 4 Fuel Filler Neck Shroud—YJ Models

(5) Disconnect fuel fill hose and fill vent hose from

filler neck (Fig. 5).

Fig. 5 Filler Neck Hoses—YJ Models

WARNING: WRAP SHOP TOWELS AROUND FUEL
HOSES TO ABSORB ANY FUEL SPILLAGE DURING
FUEL TANK REMOVAL.

Fig. 7 Fuel Tank—Remove/Install—YJ Models

(9) Lower the skid plate/fuel tank assembly
slightly and disconnect the gauge sender wire con­nector.

(10) Lower the fuel tank on transmission jack.

(11) Remove tank strap nuts to remove tank from
skid plate.

J FUEL SYSTEM 14 - 15

INSTALLATION—YJ MODELS

(1) Place tank into skid plate. Wrap straps around
tank with strap bolts inserted through holes in skid
plate. Tighten strap nuts to 7.3 Nzm (65 in. lbs.) torque.

(2) Raise skid plate/fuel tank until gauge sender wire
connector can be connected to harness connector.

(3) Finish raising skid plate/fuel tank assembly
into position. Tighten mounting nuts to 16 Nzm (12
ft. lbs.) torque. Remove transmission jack.

(4) Connect fuel fill hose and fill vent hose to filler
neck. Tighten hose clamps.

(5) Connect vent hose to vent tube.

(6) Connect fuel supply hose to the supply tube and
fuel return hose to return tube. Tighten hose clamps.

(7) Install fuel filler neck shroud with push clips.

(8) Lower vehicle.

(9) Fill fuel tank. Install filler cap.

(10) Connect negative battery cable to battery.

(11) Start vehicle and inspect for leaks.

FUEL GAUGE SENDING UNIT

The fuel gauge sending unit is attached to the fuel
pump module. Refer to Fuel Pump Module in the
Fuel Delivery System section of this group.

controlled conditions). The plunger seats in the guide
plate at the orifice preventing liquid fuel from reaching
the EVAP canister. This is done if bottom of plunger is
contacted by fuel sloshing in tank when vehicle is cor­nering.

In the event of accidental vehicle rollover, the valve
is inverted. In this position the plunger is forced
against the guide plate and raw fuel is prevented
from flowing through the valve orifice into the fuel
tank vent tube.

FUEL TANK PRESSURE RELIEF/ROLLOVER VALVE

The fuel tank is equipped with a pressure relief/
rollover valve (Fig. 8). The dual function valve will
relieve fuel tank pressure and prevent fuel flow
through the fuel tank vent tubes in the event of ac­cidental vehicle rollover.

Fig. 9 Pressure Relief/Rollover Valve Operation

REMOVAL

WARNING: THE FUEL SYSTEM IS UNDER A CON­STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING THE PRESSURE RELIEF/
ROLLOVER VALVE, THE FUEL SYSTEM PRESSURE
MUST BE RELEASED. REFER TO THE FUEL PRES­SURE RELEASE PROCEDURE IN THIS GROUP.

(1) Disconnect negative battery cable.
(2) Remove the fuel filler cap and drain fuel tank.

Refer to Fuel Tank Removal.

(3) Remove fuel tank. Refer to Fuel Tank Removal.

(4) The rollover valve is seated in a grommet. Re­move by prying one side upward and then roll the
grommet out of tank (Fig. 8).

Fig. 8 Valve Location—Typical

The valve consists of a plunger, spring and orifice/
guide plate (Fig. 9). The valve is normally open allowing
fuel vapor to vent to the EVAP canister. Here it is
stored until it can be consumed by the engine (under

INSTALLATION

(1) Start one side of grommet into opening in fuel
tank. Using finger pressure only, press valve/grom­met into place.

(2) Install fuel tank. Refer to Fuel Tank Installation.

(3) Fill fuel tank. Install fuel tank filler cap.

(4) Connect negative battery cable.

(5) Start vehicle and check for leaks.

14 - 16 FUEL SYSTEM J

ACCELERATOR PEDAL AND THROTTLE CABLE

GENERAL INFORMATION

The accelerator pedal is connected to the throttle body
linkage by the throttle cable. The cable is protected by a
plastic sheathing and is connected to the throttle body
linkage by a ball socket. It is connected to the upper part
of the accelerator pedal arm by a plastic retainer (clip)
(Fig. 10). This retainer (clip) snaps into the top of the ac­celerator pedal arm. Retainer tabs (built into the cable
sheathing) (Fig. 10) fasten the cable to the dash panel.

Dual throttle return springs (attached to the throt­tle shaft) are used to close the throttle.

CAUTION: Never attempt to remove or alter these springs.

ACCELERATOR PEDAL

CAUTION: Be careful not to damage or kink the ca­ble core wire (within the cable sheathing) while ser­vicing the accelerator pedal or throttle cable.

REMOVAL

(1) From inside the vehicle, hold up accelerator pedal.
Remove plastic cable retainer (clip) and throttle cable
core wire from upper end of accelerator pedal arm (Fig.

10). Plastic cable retainer (clip) snaps into pedal arm.

(2) Remove accelerator pedal mounting bracket
nuts. Remove accelerator pedal assembly.

INSTALLATION

(1) Place accelerator pedal assembly over studs
protruding from floor pan. Tighten mounting nuts to
5Nzm (36 in. lbs.) torque.

(2) Slide throttle cable into opening in top of pedal

arm. Push plastic cable retainer (clip) into accelera­tor pedal arm opening until it snaps into place.

(3) Before starting engine, operate accelerator

pedal to check for any binding.

THROTTLE CABLE

REMOVAL

(1) From inside the vehicle, hold up accelerator pedal.
Remove plastic cable retainer (clip) and throttle cable
core wire from upper end of accelerator pedal arm (Fig.

10). Plastic cable retainer (clip) snaps into pedal arm.

(2) Remove the cable core wire at pedal arm.

(3) From inside the vehicle, pinch both sides of the
cable housing retainer tabs (Fig. 10) at the dash
panel. Remove cable housing from dash panel and
pull into the engine compartment.

(4) Remove cable from clip on the engine cylinder
head (valve) cover.

(5) Remove the throttle cable ball end socket at
throttle body linkage (snaps off) (Fig. 11).

(6) Remove throttle cable from throttle body mount­ing bracket by compressing retainer tabs and pushing
cable through hole in bracket. Remove throttle cable
from vehicle.

INSTALLATION

(1) Slide throttle cable through hole in throttle body
bracket until retainer tabs lock into bracket. Connect
cable ball end to throttle body linkage ball (snaps on).

(2) Snap cable into clip on the engine cylinder
head (valve) cover.

(3) Push other end of cable through opening in
dash panel until retaining tabs lock into panel.

(4) From inside drivers compartment, slide throttle
cable core wire into opening in top of accelerator
pedal arm. Push cable retainer (clip) into pedal arm
opening until it snaps in place.

(5) Before starting engine, operate accelerator
pedal to check for any binding.

Fig. 10 Accelerator Pedal Mounting—Typical Fig. 11 Throttle (Accelerator) Cable—Typical