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 NOR-
MALLY RIDE HEIGHT.
CAMBER
The wheel camber angle is preset. This angle is not
adjustable and cannot be altered.
CASTER
Before checking the caster of the front axle for cor-
rect angle, be sure the axle is not bent or twisted.
Road test the vehicle, make left and right turns. If
the steering wheel returns to the center position un-
assisted, the caster angle is correct. If steering wheeldoes not return toward the center position unas-
sisted, 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.
TOE POSITIONÐXJ VEHICLES
The wheel toe position adjustment should be the fi-
nal adjustment.
(1) Start the engine if equipped with power steer-
ing. Turn wheels both ways before straightening the
Fig. 2 AdjustmentÐYJ Vehicles
Fig. 3 AdjustmentÐXJ Vehicles
Fig. 4 Steering LinkageÐXJ (LHD)
2 - 8 FRONT SUSPENSION AND AXLEJ
wheels. Secure the steering wheel with the front
wheels in the straight-ahead position. Turn off the
engine.
(2) Loosen the adjustment sleeve clamp bolts (Fig.
4, 5).
(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.
6) 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 specifi-
cations. Position the clamp bolts as shown (Fig. 6)
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 Steering LinkageÐXJ (RHD)
Fig. 6 Drag Link and Tie Rod Clamp Location (LHD)
JFRONT SUSPENSION AND AXLE 2 - 9
TOE POSITIONÐYJ VEHICLES
The wheel toe position should be the final front
wheel alignment adjustment. In all instances follow
the equipment manufacturer's recommended proce-
dure.
(1) Start the engine if equipped with power steer-
ing. Turn wheels both ways before straightening the
wheels. Secure the steering wheel with the front
wheels in the straight-ahead position. Turn off the
engine.
(2) Loosen the adjustment sleeve clamp bolts on
the tie rod (Fig. 7).The tie rod and adjustment sleeve have both
right and left hand threads to provide equal ad-
justment 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) Complete the adjustment. Position the drag
link clamp bolts as shown. Tighten the bolts to 49
Nzm (36 ft. lbs.) torque.
Fig. 7 Steering Linkage
YJ Vehicles
ALIGNMENT SPECIFICATIONSÐXJ VEHICLESALIGNMENT SPECIFICATIONSÐYJ VEHICLES
2 - 10 FRONT SUSPENSION AND AXLEJ
XJ FRONT SUSPENSION
INDEX
page page
Axle Bushing Replacement.................. 12
Coil Spring.............................. 14
Lower Suspension Arm..................... 13
Service Information........................ 11
Shock Absorber.......................... 13Spring and Shock Diagnosis................. 13
Stabilizer Bar............................ 11
Track Bar............................... 11
Upper Suspension Arm..................... 12
SERVICE INFORMATION
Periodic lubrication of the steering system and sus-
pension components is required. Refer to Group 0,
Lubrication And Maintenance for the service inter-
val.
CAUTION: Suspension components with rubber
bushings should be tightened with the vehicle at
normal height. It is important to have the springs
supporting the weight of the vehicle when the fas-
teners are torqued. If springs are not at their normal
ride position, vehicle ride comfort could be affected
and premature bushing wear may occur. 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.
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 re-
taining 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.
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 stabi-
lizer bar and axle brackets (Fig. 2). Tighten the nut
at the connecting links at the axle bracket to 95 Nzm
(70 ft. lbs.) torque.
Fig. 1 Track Bar (LHD)
JFRONT SUSPENSION AND AXLE 2 - 11
YJ FRONT SUSPENSION
INDEX
page page
Leaf Spring.............................. 16
Leaf Spring Eye Bushing Replacement......... 17
Service Information........................ 15
Shock Absorber.......................... 16Spring and Shock Diagnosis................. 15
Stabilizer Bar............................ 15
Track Bar............................... 15
SERVICE INFORMATION
Periodic lubrication of the steering system and sus-
pension components is required. Refer to Group 0,
Lubrication And Maintenance for the service inter-
val.
CAUTION: Suspension components with rubber
bushings should be tightened with the vehicle at
normal height. It is important to have the springs
supporting the weight of the vehicle when the fas-
teners are torqued. If springs are not at their normal
ride position, vehicle ride comfort could be affected
and premature bushing wear may occur. Rubber
bushings must never be lubricated.
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.
STABILIZER BAR
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the retaining nut from the connecting
link bolt (Fig. 2).
(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 usu-
ally 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.
Fig. 1 Track Bar
JFRONT SUSPENSION AND AXLE 2 - 15
MODEL 30 AXLE AND TUBE AXLE (2WD)
INDEX
page page
Axle Bushing Replacement.................. 34
Axle ShaftÐCardan U-Joint.................. 26
Backlash and Contact Pattern Analysis......... 45
Cleaning/Inspection........................ 37
Differential and Pinion Measurement........... 40
Differential Assembly....................... 38
Differential Disassembly.................... 35
Differential Installation...................... 44
Differential Removal....................... 34
Differential Shim Pack Measurement and
Adjustment............................ 43
Drive Axle Assembly ReplacementÐXJ Vehicles . . 23
Drive Axle Assembly ReplacementÐYJ Vehicles . . 24Final Assembly........................... 46
Hub Bearing and Axle Shaft................. 25
Information.............................. 22
Inner Axle Shaft Oil Seal Replacement......... 35
Lubricant Change......................... 23
Lubricant Specifications..................... 22
Pinion Gear Assembly/Installation............. 42
Pinion Gear Depth Information............... 39
Pinion Removal/Disassembly................. 36
Pinion Seal Replacement................... 25
Steering Knuckle and Ball Studs.............. 32
Vacuum Disconnect AxleÐYJ Vehicles......... 27
INFORMATION
The Model 30 front axles consists of a cast iron dif-
ferential housing with axle shaft tubes extending
from either side. The tubes are pressed into the dif-
ferential housing and welded.
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 re-
lieve internal pressure caused by lubricant vaporiza-
tion 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 dam-
age the tone wheel or the sensor.
The stamped steel cover provides a means for in-
spection 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 dif-
ferential pinion mate shaft is retained with a roll
pin. Differential bearing preload and ring gear back-
lash is adjusted by the use of shims (select thick-
ness). The shims are located between the differential
bearing cones and case. Pinion bearing preload is set
and maintained by the use of collapsible spacer.
COMMAND-TRACÐYJ 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 opera-
tion, the vacuum motor and shift fork disengages the
axle shaft splines. For four-wheel drive operation, the
vacuum motor and shift fork engages the axle
splines.
SELEC-TRACÐXJ VEHICLES
The Selec-Trac system is a non-disconnect axle.
Shifting from two-wheel to four-wheel drive is done
at the transfer case.
For XJ vehicles equipped withSelec-Tracand
ABS brake system, refer to Group 5ÐBrakes for ad-
ditional 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.
MOPARtHypoid Gear Lubricant conforms to both of
these specifications.
²The factory fill for the Model 30 axle is SAE Ther-
mally Stable 80W-90 gear lubricant.Do not use
heavier weight lubricant, this will cause axle
engagement difficulties.
²The factory installed lubricant quantity for the
NON-DISCONNECT TYPE AXLE is 1.48 L (3.13
pts.).
²The factory installed lubricant quantity for the
VACUUM-DISCONNECT TYPE AXLE is 1.65 L (3.76
pts.).
Refer to Group 0, Lubrication and Maintenance for
additional information regarding temperature range,
viscosity and fluid level.
2 - 22 FRONT SUSPENSION AND AXLEJ
CAUTION: If axle is submerged in water, lubricant
must be replaced immediately to avoid possible
premature axle failure.
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 dif-
ferential 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 MOPARtSilicone Rubber Seal-
ant to the housing cover (Fig. 1).Allow the sealant
to cure for a few minutes.
Install the housing cover within 5 minutes af-
ter applying the sealant. If not installed the
sealant must be removed and another bead ap-
plied.
(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 MOPARtHypoid
Gear Lubricant to bottom of the fill plug hole.
(9) Install the fill hole plug and lower the vehicle.
DRIVE AXLE ASSEMBLY REPLACEMENTÐXJ
VEHICLES
REMOVAL
(1) Raise the vehicle and position support stands
under the frame rails 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 5ÐBrakes.
(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. Discon-
nect 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 damper
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: Suspension components with rubber
bushings should be tightened with the vehicle at
normal height. It is important to have the springs
supporting the weight of the vehicle when the fas-
teners are torqued. If springs are not at their normal
ride position, vehicle ride comfort could be affected
and premature bushing wear may occur. 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 con-
nected. If springs are not at their usual posi-
tion, vehicle ride comfort could be affected.
Fig. 1 Typical Housing Cover With Sealant
JFRONT SUSPENSION AND AXLE 2 - 23
(6) Install the shock absorber and tighten the bolt
to 23 Nzm (17 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 damper 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 5ÐBrakes.
(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 neces-
sary.
(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 REPLACEMENTÐYJ
VEHICLES
REMOVAL
(1) Raise the vehicle and position support stands
under the frame rails behind the spring frame brack-
ets.
(2) Remove the front wheels.
(3) Remove the brake components and ABS brake
sensor (if equipped). Refer to Group 5ÐBrakes.
(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.
(9) Disconnect the tie rod from the steering
knuckle. Disconnect the steering damper 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 brack-
ets. This will allow the springs to pivot without bind-
ing 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: Suspension components with rubber
bushings should be tightened with the vehicle at
normal height. It is important to have the springs
supporting the weight of the vehicle when the fas-
teners are torqued. If springs are not at their normal
ride position, vehicle ride comfort could be affected
and premature bushing wear may occur. 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 con-
nected. If springs are not at their usual posi-
tion, 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 damper 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 5ÐBrakes.
(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 neces-
sary.
(13) Install the wheel and tire assemblies.
(15) Remove the supports and lower the vehicle.
(16) 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.
2 - 24 FRONT SUSPENSION AND AXLEJ