Rubicon Express RE8300 User Manual

RUBICON EXPRESS. 3290 MONIER CIR., RANCHO CORDOVA, CA. 95742 916-473-4600

INSTALLATION INSTRUCTIONS FOR:

RE8300 4.5” ZJ EXTREME DUTY LONG ARM SYSTEM

Congratulations on purchasing the ultimate suspension upgrade available for the 1993-1998 Jeep ZJ Grand Cherokee. This kit will transform
your ZJ into a formidable trail machine with excellent road manners, much the same way our TJ long arm kit trans forms the Wrangler.

Application Notes:

1. Lift heights over 3.5” may require modifications to the front and/or rear drive shaft, especially the full time NP249 transfer case –
see slip yoke vibration in Troubleshooting before proceeding.

2. This kit requires modifications to the exhaust s ystem. Generally, after the suspension is install e d , plan on a shop installing a

system from about the factory crossmember on back with a smaller muffler.

.

Safety Warning:

Suspension systems or components that enhance the off-road performance of your vehicle may cause it to handle differently, on and off-road, than it did from
the factory. Care must be taken to prevent loss of control or vehicle rollover during sudden maneuvers. Failure to drive the vehicle safely may result in serious
injury or death to driver and passengers. We recommend you always wear your seat belt, drive safely and avoid quick turns and other sudden maneuvers.
Constant maintenance is required to keep your vehicle safe. Thoroughly inspect your vehicle before and after every off-road use.

Installation Warning:
We recommend that certified technicians perform the installations of our products. Attempts to install these products without knowledge or exper i en ce may
jeopardize the safety of the vehicle. These instructions only cover the installation of our products and may not include factory procedures for disassembly and
reassembly of factory components. Read instructions from start to finish and be sure all parts are present before disassembling the vehicle. Included
instructions are guidelines only for recommended procedures and in no way are meant to be definitive. Installer is responsible to insure a safe and controllable
vehicle after performing modifications. Do not perform test drives on public roads with partially completed installations. Always double and triple check your
work before use.

KIT CONTENTS

RE1150 Rear Sway Bar End Links
RE1141 Gen2 Sway Bar Disconnects
RE1345 Front Coil Springs
RE1350 Rear Coil Springs
RE1380 Front 2” Bottom Bump Stop Extensions
RE1390 Rear 2” Bump Stop Extensions
RE1550 Front Brake Lines
RE1604 Rear Track Bar Bracket
RE1650 Rear Adjustable Track Bar
RE1660 Front Extreme Duty Track Bar
RE1665 Front Extreme Duty Track Bar Bracket
RE4000 Front Lower Left Extreme Duty Control Arm
RE4010 Front Lower Right Extreme Duty Control Arm
RE4020 Front Upper Extreme Duty Control Arms
RE4030 Rear Lower Extreme Duty Control Arms
RE4040 Rear Upper Extreme Duty Control Arm
RE9950 Front 3-piece crossmember (’93-’95 tranny mount, cross piece, 2-uniframe plates, 2-side braces, 4-bolting strip , hdwr) s
RE9960 Rear 3-piece crossmember (cross piece, 2-uniframe mounts, 2-side braces, 2-bolting strips, 2-nut strips, hdwr)

TYPICAL TOOLS REQUIRED

1-1/8” hole saw for steel, ½” drill motor & drill bits, angle grinder,
Basic mechanical hand tools and T-55 Torx head bit along with standard Torx head wrench set,
Floor jack & jack stands (2 Pair),
Welder, Plasma cutter, or reciprocating saw w/meta l cutting blades, or cutting wheels for angle grinder

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PRE INSTALLATION NOTE:

Control arm bushings are pre-lubed during initial assembly at Rubicon Express. As general mainte nance the control arm bushings should be
lubed with a silicone base grease

The Super-flex joints are also pre-lubed during initial assembly at Rubicon Express. As general maintenance the super-flex joints should be
greased as needed and the outer spanner nut tightened on the joint. Any type of grease will work on the Super-flex joints. Spanner nut
tools are available through Rubicon Express (RE3771 & RE3772) if needed for tightening of the joints.

as needed. Silicone base grease can be purchased at your local auto parts store.

INSTALLATION OVERVIEW

The installation process can be broken down into the following tasks:

1. Removal of factory lower control arm mounts from uniframe.

2. Front 3- piece crossmember.

3. Rear 3- piece crossmember.

4. Control arms.

5. Bump stops and coils.

6. Track bars and sway bar links.

7. Brake lines and shocks.

8. Final detailing and adjustments.

Step 1 - Removal of factory lower control arm mounts on frame.

A. First, support vehicle by uniframe (preferably on a lift) and work on a stable level surface. Support axles with jack stands and

remove the following components; shocks, track b a rs, sway b a r end links, coil springs, control arms, bump stops, front brake
hoses and exhaust from crossmember on back. It may be helpful to only disconnect axle end of brake hoses and pinch-off hoses
with vise grips to minimize fluid loss until new SS hoses are installed in Step 7. NOTE: Coil springs can be removed without
compressors if enough distance is generated between the axle and frame. If a lift is not being used, it may be easier to do this
one side at a time on one axle at a time.
CAUTION: If using coil spring compressors, use extreme care as they will be holding a lot of potential energy and can release
violently.

B. Cut off the (4) factory lower control arm mounts from the uniframe. Use extrem e care as not to damage the uniframe, or cut into

existing brake, fuel, or electrical lines.

C. Grind rough areas smooth and repaint – refer to Photo 1 and 2 for typical front and rear bracket removal.

Photo 1

Photo 2

Step 2 - Front 3-piece crossmember

A. First, support transmission/transfer case and remove factory crossmember.
B. Refer to Photo 3 for exploded view of all pieces of one end of the complete crossmember. Loosely assemble the main 3-piece

crossmember with the four supplied 1/2” bolts. The three main pieces consist of the two “9-hole” uniframe plates and the
transmission/control arm mount cross piece. For ’93-’95 vehicles, loosely install the transmissio n mount to the crosspiece (’96-’98
bolts directly to cross piece). Loosely bolt assembly up into position with the four factory crossmember bolts – refer to photo 4.
Align uniframe plates so their nine holes can be transferred through the pinch welds along the inside of the uniframe rails and
tighten the four bolts to hold in position.

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Photo 3

C. Place 9-hole bolting strips on top of the pinch welds and clamp into position so the holes align with the holes in the uniframe

D. Loosely bolt side braces to uniframe plates with supplied 3/8” flat head bolts so that the notch in the outer leg surrounds the

E. Weld the very front edge of the uniframe plates to the unifram e (edge at top of Photo 3). This is the thick area of the uniframe

F. If so equipped, the factory transfer case skid plate may be attached to the new cross piece.

Photo 4

plates. Drill through pinch weld at front holes of uniframe plates and loosely secure up through the bolting strips with supplied
5/16” flat head bolts. Repeat drilling and bolting for remaining uniframe plate holes. Note that there are two holes in the
uniframe plates that can’t be accessed with cross piece installed, so remove cross piece to drill and bolt these. Reinstall cross
piece.

gutter drain - refer to Photo 5. Place 3-hole bolting strips on outside of the pinch welds and clamp into position so the holes align
with the holes in the side braces. Drill through pinch weld at front holes of bolting strips and loosely secure through the side
braces with supplied 5/16 “ hex head bolts. Next, drill and secure back hole, then middle hole – refer to Photo 6. Tighten all
crossmember and transmission mount bolts at this time.

where the factory control arms were removed. Also, plug-we ld the 2 holes in the rear tab of the uniframe plate to the uniframe
(2-hole tab at bottom of Photo 3). The three sides of this tab can be welded to the uniframe as well. CAUTION - a certified w elder
that can weld thick metal to thin should d o this and care should be taken to protect wiring, fuel lines, brake lines, etc, and to not
ignite coatings etc. on fire.

Photo 5 Photo 6

Step 3 - Rear 3-piece frame crossmember

A. Refer to Photo 7 for exploded view of all the pieces of one end of the complete crossmember. Locate right uniframe moun t

over uniframe rail with lower control arm mount open toward the rear and angled side brace mounting plate pointing out
toward rocker panel. Slide uniframe mount back until it stops against the outer unibody mount. Hold mount tight against
frame bottom and center punch frame through all five mounting ho les. Remove mount and drill center hole only
1/8” hole saw, then drill the remaining four with a 3/ 8” bit. Slide the 5-Pem-nut strip up into the 1-1 / 8” hole (with nuts on
top) and position so nuts align with the five frame holes. It may be helpful to hook a stiff wire or threaded stud up through
the center hole and pull down to hold the strip while getting the first few bolts up through the mount. Loosely fasten the
mount with supplied 3/8” flat head bolts – refer to Photo 8. Repeat for left frame mount.

with a 1-

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