Allison Transmission 4000, B 500 Service Manual

TECHNICIANS’ GUIDE

INSPECTION AND ANALYSIS OF THE

ALLISON 4000 & B500

PRODUCT FAMILIES

GN4065EN

(5/05)

INSPECTION AND ANALYSIS OF THE

ALLISON 4000/B 500 PRODUCT FAMILIES

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

NOTICE: This guide is intended

for use by technicians skilled in diagnosis and repair of automatic transmissions. Contact an authorized Allison Transmission service outlet for further information or clarification if required. All specifications provided in this manual are subject to change without notice.

Glossary Of Terms . . . . . . . . . . . 2

Introduction T o

Inspection & Analysis . . . . . . . . 3

General Inspection Guidelines for

Cast Parts & Machined

Surfaces . . . . . . . . . . . . . . . . . . 4

Gears . . . . . . . . . . . . . . . . . . . . 5

Splines . . . . . . . . . . . . . . . . . . . 6

Bearings . . . . . . . . . . . . . . . . 7-8

Bushings . . . . . . . . . . . . . . . . . 9

Retaining Rings . . . . . . . . . . 10

Thrust Washers . . . . . . . . . . . 11

Clutch Plates . . . . . . . . . . 12-13

Springs . . . . . . . . . . . . . . . . . 14

Valves and Valve Bores . . . . 15

Control Module . . . . . . . . . . 16-21

Torque Converter

Module . . . . . . . . . . . . . . . . . 22-27

Torque Converter

Housing Module . . . . . . . . . 28-30

Standard Rear Cover and

P3 Planetary Module . . . . . 31-38

Retarder Module . . . . . . . . . 39-42

Close Ratio Main

Shaft Module . . . . . . . . . . . . . . 43

Wide Ratio Main

Shaft Module . . . . . . . . . . . . . . 44

P2 Planetary Module . . . . . 45-46

P1 Planetary Module . . . . . 47-48

Front Support & Oil

Pump Module . . . . . . . . . . . 49-52

Rotating Clutch Module . . . 53-58

C3/C4 Clutch Module . . . . . 59-64

Main Housing . . . . . . . . . . . 65-66

C6 Adapter Housing . . . . . . 67-69

Wear Limits and

Spring Data . . . . . . . . . . . . . 70-77

Abrade - Scrape off Battering - Wear or damage due to

hard usage or repeated blows

Brinelling - Permanent deformation

of a bearing surface where rollers or balls contact a race; Results from excessive load or impact; Characterized by indentations on a bearing surface

Burr - Sharp metal extending

beyond normal surface

Chipped - Having a small piece

broken off

Cone - A shape whose base is a

circle and whose sides taper up to a point

Crimped - Pinched or pressed

together tightly

Crocus cloth - Fine grit cloth Discoloration - Change in color Distortion - Change from original

shape

Erosion - Gradual uneven removal

of material

Fracture - A break or crack Gall - Wear between parts such

that metal transfer occurs

Grooves - Long narrow

depressions

Inadequate - Not enough Light Stoning - Using a

medium India oilstone to remove material

Metal T ransfer - Metal from one

component embedded in a mating component

Nick - Small notch Pit - Local areas where material has

been removed

Porosity - Porous area where air,

fluid, or light may pass through

Score - Deep scratch Scuff - Wear due to two moving

parts coming together with no lubricant

Spalled - Damage characterized by

metal flaking or breaking down on a wear surface; Similar to pitting damage

Stripped - Threads broken or

damaged so part will not hold torque

TAN - Total Acid Number;

Oil acidity should not change by more then 3 from the new fluid TAN when oil sampling is used to determine oil change intervals

Twisted - Bent from original shape

ALLISON 4000/B500 PRODUCT FAMILIES

GLOSSARY OF TERMS

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

The Technicians’ Guide is intended to provide additional guidance with the inspection and analysis of transmission parts.

This guide should be used by technicians who overhaul Allison 4000/B 500 automatic transmissions in conjunction with the 4000/B 500 Service Manual

(SM2457EN) when inspecting parts

to determine their serviceability and reuse.

General Rework Guidelines

Replace parts that cannot be re-worked as outlined in this manual and Service Manual SM2457EN. A soft stone or crocus cloth can be used to attempt removal of “high spots” from transmission parts. After the attempted rework, the part must meet specification if it is going to be reused. Some seal surfaces (for

example the output yoke sealing surface and the converter pump hub sealing surface) cannot be reworked.

Both of these seal surfaces have a controlled finish that can result in a fluid leak if the part is altered by rework.

ALLISON 4000/B500 PRODUCT FAMILIES

INTRODUCTION TO INSPECTION & ANALYSIS

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Replace housings or other cast

parts that are cracked or broken. Inspect clutch housing sealing surfaces for imperfections that

could damage the piston seals or interfere with mating parts. Inspect threaded holes for bad threads. Clean damaged threads with the correct size tap.

B. Inspect all machined surfaces

for damage that could cause fluid leakage. Inspect mounting faces and bores for damage.

C. Inspect all fluid passages for

obstructions, porosity, broken lands, cracks and land surface imperfections.

D. Replace housings that have

splines worn beyond wear limits. Refer to the Wear Limits Table (7-1) in Service Manual SM2457EN.

NOTE: Some parts have Spiralock®

threaded holes . A standard tap will eliminate the locking feature requiring the reworked part to be replaced. For repair, use a Spiralock® tap to repair Spiralock® threaded holes. As of this printing, the following parts have Spiralock® threaded holes:

Torque converter front cover flexplate adapter bolt holes and lockup clutch backplate bolt holes.

Output shafts using a single bolt for flange or yoke retention.

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR CAST PARTS & MACHINED SURFACES

C. Fluid

Passages

A. Cast

Part

A. Housings

D. Splines

C. Fluid

Passages

B. Machined

Surfaces

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR

GEARS

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Inspect gears for damaged or

broken teeth. Inspect gear teeth for wear that has changed the original tooth shape. If this condition is noted, replace the gear. Inspect gears for load pattern and signs of distress. Any signs of distress indicate the gear may fail during operation. Reusing distressed gears is an individual customer decision based on experience. Backlash cannot be used to establish critical gear wear. Pits, scuffs, scores or galling are typically evident long before backlash exceeds specification.

B. Inspect the thrust face of gears

for damage. If these defects cannot be removed with a soft stone, replace the gear.

Check gears for damaged or missing teeth.

A. Gear

Teeth

B. Thrust Face

Surface

A. Gear

Teeth

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Inspect splined parts for

damage. Remove burrs with a soft stone. Spline wear is not considered harmful except where it affects the fit of the splined parts. Spline wear is determined by comparing feeler gauge thickness with the thickness of the worn area on the spline. Replace parts having excessive spline wear. The maximum movement allowed at the splines is

0.38 mm (0.015 inches) if not otherwise listed in Wear Limits Table 7-1 in Service Manual SM2457EN. Do not reuse a splined part that exceeds the published maximum spline wear. Backlash cannot be used to establish critical spline wear. Accurate backlash measurement requires the mating parts to be concentrically located.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR SPLINES

Inspect splined parts for burrs, damage and excessive wear.

A. Splines

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Replace the bearing if any

rollers/balls are rusted. Replace the

bearing if balls/rollers have a feeling of looseness in the retainer or race compared to a new bearing. Replace the bearing if balls/rollers are discolored from heat, lack of lubrication or debris lapping in the balls/rollers. Replace the bearing if the balls/rollers are worn, galled or abraded. Replace the bearing if it catches or feels rough after being thoroughly cleaned.

B. Replace the bearing if any

races are rusted. Replace the

bearing if the bearing balls/rollers have a feeling of looseness in the raceway compared to a new

bearing. Replace the bearing if races are discolored from heat, lack of lubrication or debris lapping in the race. Replace the bearing if the races are worn, galled or abraded. Replace the bearing if it catches or feels rough after being thoroughly cleaned.

C. Replace the bearing if any

retainer or retainer clip is fractured, bent, dented or missing. Replace the bearing if any retainer is rusted. Replace the bearing if there is a feeling of looseness between the retainer and ball/roller compared to a new bearing. Replace the bearing if it catches or feels rough after being thoroughly cleaned.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR

BEARINGS

A. Rollers

B. Bearing

Race

C. Retainer

B. Bearing

Race

B. Bearing Race

(continued)

C. Retainer

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

General Bearing Handling & Storage

Dirt is the greatest single enemy of any antifriction bearing. Cleanliness - using clean tools in a clean environment - is at the top of the list of good service techniques. Keep bearings sealed in

original containers. Do not allow anyone to open boxes and handle bearings. A new bearing, if not protected, can quickly pick up enough dust even in an apparently clean place to seriously affect its life and operation. Minimize the possibility of rusting or lubricant aging in storage by using the oldest bearings in stock first.

If any part of a bearing assembly has been compromised, replace all detail parts in the assembly (example - races, retainers and the bearing itself). Most bearings fail from preventable causes. Follow a regular system for inspection. Look for bearings with obvious damage first.

General Bearing Inspection

Do not try to judge the condition of a bearing until after cleaning. Do not spin bearings while cleaning them. Rotate them slowly while washing. Do not spin any bearings with air pressure. Put bearings under axial pressure while rotating to bring the balls and races firmly in contact with each other. For single row angular contact bearings, pressure must always be applied on thrust faces.

When immersing in solvent, place bearings in a wire basket so there is plenty of space for cleaner to reach all parts. Tanks should have a screened false bottom to prevent settled debris from being stirred up into the bearings. Agitate the basket frequently until grease, oil or sludge is thoroughly loosened and can be flushed out. Blow solvent out of bearings using dry, filtered air. Be careful not to spin the bearing using air pressure. Lubricate bearings immediately after drying to avoid rust.

NOTE: Wear eye protection and

follow the appropriate safety guidelines when using solvents to clean components.

Badly discolored rollers and races are usually a sign of inadequate lubrication. Replace badly discolored bearings. Moderately discolored rollers, cages and races do not necessarily mean that the bearing needs replacement.

Technicians should always try to determine the root cause of failure when inspecting failed components. It’s important the root cause be identified and repaired to avoid the same failure in the future. Bearings

should be replaced for the following reasons:

Rusted rollers, balls or raceways -

rusted rollers, balls or raceways are usually caused by water passing worn or defective seals, or by condensation inside the housing.

Fractured races - a fractured race

can be caused by forcing a cocked bearing on or off a shaft. An excessively tight press fit can also cause a race to fracture.

Worn, galled or abraded surfaces - worn, galled or abraded

surfaces on a bearing may be the result of a loose fit on a shaft or in a housing. A locked bearing spinning on a shaft or in a housing can also create this type of damage.

General feeling of roughness -

inspect for a general feeling of roughness which remains unchanged by thorough cleaning. This condition generally indicates damage to raceways or rollers caused by dirt, pitting, brinelling or corrosion.

Catchy feeling - inspect for a

catchy feeling at one or more points which repeated flushing will not remove. This condition generally indicates a spalled or fatigued spot on the race. Thorough flushing is necessary to be sure the catchy or rough feeling is not caused by foreign debris in the bearing.

Excessive looseness - inspect for

excessive looseness which indicates lapping by dirt or an abrasive contaminate in the lubricant. If in doubt, compare the end play against the end play of an identical new bearing. The races, balls and rollers will appear dull gray when lapped by dirt.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR BEARINGS

(continued)

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Inspect bushings for wear

beyond service limits. Replace any bushing which is excessively worn. Inspect bushings for discoloration and surface damage due to lack of lubrication. Replace any bushing which is damaged.

General Bushing Information

Mechanically, bushings are the simplest type of journal bearing and are often referred to as “plain” bearings. A bushing is simply a sleeve of bearing material, such as bronze or aluminum, in which a component rides. Bushing wear is strongly influenced by the quantity and condition of the lubricant. Bushing bearing surfaces are sometimes grooved to better distribute lubrication across the bearing surface.

Some bushings are susceptible to material leaching. This can be caused by oxidized oil that has turned acidic combined with heat and mechanical loading. The TAN (Total Acid Number) of the transmission oil should not change by more than 3 from the baseline (new fluid) TAN. Changing transmission oil per recommended change intervals or based on a successful oil sampling program will help prevent material leaching.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR

BUSHINGS

Bushing wear is strongly influenced by the quantity and condition of the lubricant.

A. Bushing

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Inspect retaining rings for

damage, distortion and excessive wear. Replace retaining rings if damage cannot be repaired using a soft stone or crocus cloth.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR RETAINING RINGS

Examine retaining rings for damage, distortion or excessive wear.

A. Retaining

Rings

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Replace thrust washers if they

are worn beyond service limits. Replace thrust washers if they are galled, abraded or distorted. Replace thrust washers if they are damaged due to a lack of lubrication.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR

THRUST W ASHERS

A. Thrust

Washers

Thrust Washers

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Contact

Surface

C. Oil

Groove Depth

D. Spline

Teeth

A. Inspect friction plate contact

faces and splines for excessive wear, damage and coning. Inspect the plates for burrs, pitted faces, cracks, distortion and damaged spline teeth.

B. Measure friction plate

thickness and coning. Reference the Service Manual for minimum thickness and maximum coning specifications. Do not reuse friction plates that do not meet published specifications. If reused plates are slightly coned (within specification), make sure each plate is stacked with the cone facing the same direction.

C. Measure friction plate oil

groove depth. Replace any plates that are not within Service Manual minimum groove depth specification.

D. Inspect spline teeth for

excessive wear and battering. Replace the clutch plate if damage cannot be repaired using a soft

stone or crocus cloth. Replace the clutch plate if spline teeth are broken or missing.

NOTE: Anti-freeze (glycol) and/or

water can adversely affect the bonding agent between the friction material and steel core. Replace any friction plates which have been exposed to water and/or glycol.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR CLUTCH PLATES

B. Clutch Plate

Thickness and Coning

Check Using Feeler Gauge

Thickness

Coned Plate

Flat Plate

(continued)

Oil grooves appear shallow or worn away measure plate thickness and groove depth.

Spline teeth battered and worn - may be an indication of driveline issues. Replace clutch plates and check driveline.

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

NOTE: The current clutch friction plates

were implemented April of 2000 starting with s/n 6610062126. Current clutch friction plates will have two or more missing splines. Former friction plates will either have one spline missing or none missing. Any 4000/B 500 model transmission may be updated from former C5 friction plates to current C5 frictions without recalibrating the transmission ECU. The rest of the clutches in the main housing (C1 through C4) must be updated with current friction plates if any other individual clutch besides C5 is updated from former to current friction plates. Any update from former frictions to current frictions in C1 through C4 for a 4000 Series or B500 with a WTEC II ECU will require a new ECU calibration from Allison Transmission. Any update from former frictions to current frictions in C1 through C4 for a 4000 Series or B500 with a WTEC III ECU with a calibration prior to October 25, 1999 will require an updated ECU calibration from

Allison Transmission. Do not intermix both former and current friction plates in a clutch pack.

The P3 ring gear changed to a harder ring gear on s/n 6610027070. The current P3 ring gear identifier is a groove machined around the outer diameter of the gear. The P3 ring gear with a groove identifier requires the C5 friction with two missing splines if updating from former C5 frictions. If any 4000/B500 series model without the harder ring gear (no groove on O.D.) is being updated with current C5 frictions, then it will require the C5 friction that has three missing internal splines. The C5 friction plate missing three splines will exhibit spline wear if used with the current P3 ring gear with a groove identifier on the O.D. The former P3 ring gear (no groove on O.D.) will exhibit premature wear if used with the current C5 friction with two missing internal splines. No ECU calibration is necessary for updating C5 clutch plates.

A. Inspect reaction plates for

excessive wear, warping, coning and surface damage. Replace any plate with wear exceeding service limits or with damage which cannot be repaired using a soft stone or crocus cloth..

B. Measure reaction plate

thickness and coning. Reference

the Service Manuals for minimum thickness and maximum coning specifications. Do not reuse plates that do not meet published specifications. If reused plates are slightly coned (within specification), make sure each plate is stacked with the cone facing the same direction.

C. Inspect reaction plate tangs

for damage. Replace the plate if damage cannot be repaired using a soft stone or crocus cloth.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR

(continued)

CLUTCH PLATES

A. Contact

Surfaces

B. Thickness

& Coning

(see prior page graphic)

C. Tangs

Acceptable discoloration reuse plates.

Excessive scoring replace plates.

Broken tangs replace plates.

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Inspect springs for permanent

set and wear due to rubbing adjacent parts. Replace the spring if any of these defects are identified or if the spring fails to meet published service limits. Reference the Spring Data Charts in Service Manual SM2457EN for spring identification and service limit specifications.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR SPRINGS

Inspect springs for signs of overheating, permanent set or wear due to rubbing adjacent parts.

A. Springs

Reference the Service Manual Spring Data Charts for spring identification and specifications.

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

A. Valves must be free of nicks,

burrs and scoring and operate smoothly in their bores without sticking. Dry valves must move freely in their bores by their own weight. Replace damaged valves. A soft stone or crocus cloth can be used in an attempt to repair slight irregularities.

B. Valve bores must be free of

nicks, burrs and scoring. No honing of any kind is allowed. A soft stone or crocus cloth can be used in an attempt to repair slight irregularities.

ALLISON 4000/B500 PRODUCT FAMILIES

GENERAL INSPECTION GUIDELINES FOR

VALVES & VALVE BORES

Valves should move freely in their bores, when dry, under their own weight.

Valve bores must be free of nicks, burrs and scoring.

A. Valves

B. Valve

Bores

A. Inspect the channel plate for

damage. All passages must be clear of debris. Inspect all machined surfaces for burrs, nicks or scoring. Light stoning and crocus cloth may be used to eliminate minor high spots. If a channel plate cannot be repaired so that all machined surfaces can seal correctly to their mating parts, or if thread damage cannot be repaired, replace the channel plate.

NOTE: Do not use impact guns (air

wrenches, electric impact wrenches, etc.) when working with aluminum threads or when torque sequencing bolts.

B. Inspect both

separator plates for dents,

nicks, burrs and other damage or distortion. Replace the plate if it has damage which cannot be repaired using a soft stone or crocus cloth. All passages must be clean and debris free.

A. Channel

Plate

B. Solenoid

Separator Plate

D. Internal

Wiring Harness

C. Suction

Filter Assembly

E. Rotating

Clutch Body Assembly

F. Main Valve

Body Assembly

G. Stationary Clutch

Valve Body Assembly

H. Oil Level

Sensor

ALLISON 4000/B500 PRODUCT FAMILIES

CONTROL MODULE

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

B. Separator Plate

Separator plate and gasket installed on channel plate.

(continued)

ALLISON 4000/B500 PRODUCT FAMILIES

(continued)

CONTROL MODULE

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

C. Replace the suction filter

assembly during overhaul.

D. Replace or repair the control

module wiring harness if the

wires, terminals or connectors are visibly damaged. Inspect the molded harness channel for cracks or breaks. Replace the harness if the molded channel is damaged. Check sump temperature resistance following the guidelines and specifications listed in the Service Manual and Troubleshooting Manual.

NOTE: Transmissions built prior to

S/N 6610014067 used the former design sump temperature sensor. Sensor resistance specifications

differ between the former and current designs. Be sure to use the correct resistance specification chart for the sensor being checked.

Sump Temperature Sensor (TID 2, 3)

D Solenoid (C4)

C Solenoid (C3)

E Solenoid (C5)

F Solenoid (Lockup)

Oil Level Sensor

Feed Through Stand-Off

C3 Pressure Switch

A Solenoid (C1)

Feed Through Harness

B Solenoid (C2)

G Solenoid (C2 Latch)

Identification Detail:

Internal Wiring Harness

Current TID2/TID3 Harness

Former TID1 Harness

TID1 Sump Temp. Sensor

(continued)

Dust Seal

O-Ring Seal

TID 2, 3 Sump Temp. Sensor

ALLISON 4000/B500 PRODUCT FAMILIES

CONTROL MODULE

(continued)

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

E, F, G. Valves, valve body bores

and oil passages must be free of debris, nicks, burrs, scoring and galling. Valves should move freely in their bores, when dry, under their own weight. Repair or replace valves and/or valve bodies failing to meet these requirements.

Valve body machined surfaces

must be free of debris, nicks, burrs and scoring. Light stoning of these machined surfaces is permitted to correct minor defects. Replace any valve body that cannot be repaired.

Inspect all threaded holes for damage and debris. Replace the valve body if the thread damage cannot be repaired.

NOTE: Do not use impact guns (air

wrenches, electric impact wrenches, etc.) when working with aluminum threads or when torque sequencing bolts.

Replace valve springs which are broken, permanently set or worn due to rubbing adjacent parts. Reference the Spring Data Charts in the Service Manual for spring specifications and identification.

Valve stops and retention pins must not be damaged or battered. Replace valve stops or pins which have damage that cannot be removed using a soft stone or crocus cloth.

Replace solenoids if they are visibly damaged. Proper solenoid resistance is 3 to 4 ohms measured between the two solenoid terminals. Check resistance between each solenoid terminal and the solenoid body. Replace the solenoid if resistance measures less than 100k ohms.

Supersession Information

Oil Drain Plug Redesign SIL 5-WT-98, Rev. A

Current plug is backward compatible with all control modules.

Supersession Information

Oil Level Sensor Redesign SIL 19-WT-99

Kit must be used when replacing former sensor with current sensor.

Current

Former

(continued)

Replace the C3 pressure switch if it is visibly damaged. Resistance between the two switch terminals should measure 20k ohms or higher when the switch is open (and no pressure is present). Resistance between the two terminals should not exceed 2 ohms when the switch is closed (159 kPa-255 kPa or 23-37 psi present).

H. Replace the optional oil level

sensor if it is determined it is not

functioning correctly.

ALLISON 4000/B500 PRODUCT FAMILIES

(continued)

CONTROL MODULE

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

4” Channel Plate

2” Channel Plate

Supersession Information

Suction Filter Redesign - SIL 1-WT-00

Replace the assembly during overhaul.

Current

Former

(continued)

ALLISON 4000/B500 PRODUCT FAMILIES

CONTROL MODULE

(continued)

B Solenoid (C2)

F Solenoid (Lockup)

A Solenoid (C1)

Rotating Clutch V alve Body

Solenoid Regulator Valves

C3 Pressure Switch

Solenoid Regulator Springs

Identification Detail: Rotating Clutch Valve Body Assembly

D Solenoid (C4)

C Solenoid (C3)

E Solenoid (C5)

Solenoid Regulator Valves

Solenoid Regulator Springs

Stationary Valve Body

Overdrive Knock Down V alve

Identification Detail: Stationar y Clutch Valve Body Assembly

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

Accumulator Relay V alve

(continued)

ALLISON 4000/B500 PRODUCT FAMILIES

(continued)

CONTROL MODULE

Converter Regulator Valve

Converter Regulator Spring

Converter Regulator Valve Stop

Main Regulator Valve Stop

Control Main Valve

Control Main Valve Spring

Control Main Valve Stop

Main Regulator Valve Spring

Lube Regulator Valve

Lube Regulator Valve Spring

Lube Regulator Valve Stop

Main Regulator Valve

Lockup Valve

Lockup Valve Spring

Lockup Valve Stop

C1 Latch Valve

C2 Latch Valve

Main Valve Body

G Solenoid

C1 Latch Valve Spring

C2 Latch Valve Spring

C1 Latch Valve Stop

C2 Latch Valve Stop

Exhaust Backfill Valve Stop

Exhaust Backfill V alve

Supersession Information

Converter Regulator Valve Stop Redesign SIL 12-WT-99

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

Identification Detail: Main Valve Body Assembly

Current Stop

Former Stop

(continued)

A. Converter

Pump Exterior

Inspect the converter pump

exterior for dents and sealing

surface damage. Replace the converter pump if damage cannot be remove with a soft stone or crocus cloth.

B. Inspect the converter pump

hub for damage and excessive wear.

Minimum pump hub diameter is

88.99 mm (3.504 inch). Inspect the pump hub tangs for cracks, impact damage or broken tangs. Maximum allowable tang step wear is 0.31 mm (0.012 inch). On PTO-equipped models, check the splines inside the hub for wear and damage. Maximum spline wear is 0.38 mm (0.015 inch).

NOTE: Do not use crocus cloth on

the converter pump hub. Polishing the hub with crocus cloth can cause improper input seal performance resulting in fluid leakage.

NOTE: Pump hub tang breakage or

deformity accompanied by charging

pump bushing failure and ground sleeve wear is often caused by poor transmission fluid condition due to improper maintenance intervals. Observation of proper fluid change intervals is key to optimum transmission life.

Inspect the pump hub tangs for cracks, impact damage and broken tangs.

B. Drive Hub

B. Drive

Hub

Model Identifiers (see chart)

Torque Converter Model Designation

Front Cover Sticker and Converter Paint Dot Color (Exterior Marker)

Engraved Letter Identifiers (Torus Ring of Converter Pump) Ink Stamped Letter (Exterior of Converter Pump)

Number of Stator Blades Paint Dot Color on Stator

TC-521

Green

None

TC-531

Pink

None

TC-541

Blue

None

TC-551

Orange

None

TC-561

Yellow

None

4000 Product Family Torque Converter Identification Chart

(continued)

ALLISON 4000/B500 PRODUCT FAMILIES

TORQUE CONVERTER MODULE

 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

C. Inspect the torque converter

front cover mounting faces for

damage. Inspect the flexplate adapter bolt holes for stripped or damaged threads.

D. Inspect the front cover pilot

for damage and wear. Maximum pilot diameter is 61.77 mm (2.432 inches). Inspect the torque converter end plug and the retaining bolt for stripped or damaged threads. Verify that the correct turbine shaft selective shim is installed following the Service Manual procedures.

E. Inspect the engine starter ring

gear for chipped, worn or broken

teeth.

F. Inspect the flexplate adapter

mounting faces for surface damage.

Replace the adapter if damage cannot be repaired using a soft stone or crocus cloth. Inspect the flexplate adapter bolt holes fro stripped or damaged threads. Clean damaged threads using the correct size tap. Replace the adapter if damage cannot be repaired.

NOTE: The flexplate adapter bolt

holes use Spiralock® threads. A Spiralock® tap must be used when repairing damaged threads. Using a standard tap will destroy the locking feature. If this occurs, the torque converter front cover must be replaced.

ALLISON 4000/B500 PRODUCT FAMILIES

TORQUE CONVERTER MODULE

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 2005 General Motors Corporation.

ALLISON TRANSMISSION TECHNICIANS’ GUIDE

C. Front

Cover Mounting Face

Current Plug

E. Ring

Gear

D. Pilot

F. Flexplate

Adapter

Converter Retaining Bolt

Turbine Shaft Selective Shim

Supersession Information

Converter Plug and Front Cover Update SIL-21-WT-98

Model Identifiers (see chart previous page)

The current front cover has a threaded pilot to accept the current converter plug. Plugs are not interchangeable

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