(5) Extra close attention should also be given to
the hood latch components to ensure proper function-
ing.
HEADLAMPS
MAINTENANCE SCHEDULE
Every six months check the headlamp beams to en-
sure that the headlamp beams are correctly posi-
tioned.
AIM ADJUSTMENT
Refer to Group 8L, Lamps for headlamp aim ad-
justment procedures.
SPEEDOMETER CABLE
SERVICE INFORMATION
Speedometer cable lubrication is not necessary. For
service information involving noisy cables, refer to
Group 8E, Instrument Panel and Gauges.
BODY LUBRICANT SPECIFICATIONS
Fig. 11 Hood Hinge LubricationÐXJ Vehicles
JLUBRICATION AND MAINTENANCE 0 - 33
FRONT WHEEL ALIGNMENT
INDEX
page page
Alignment Measurements and Adjustments....... 8
General Information........................ 5Pre-Alignment Inspection.................... 6
GENERAL INFORMATION
Front wheel alignment involves the correct posi-
tioning of the wheels in relation to the vehicle. The
positioning is accomplished through suspension and
steering linkage adjustments. An alignment is con-
sidered essential for efficient steering, good direc-
tional 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.
²CASTER is the forward or rearward tilt of the
steering knuckle from vertical. Tilting the top of the
knuckle rearward provides positive caster. Tilting thetop of the knuckle forward provides negative caster.
Caster is a directional stability angle. This angle en-
ables the front wheels to return to a straight ahead
position after turns (Fig. 1).
²CAMBER 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 in-
side or outside edge of the tire (Fig. 1). The angle is
not adjustable, the damaged component(s) must be
replaced to correct mis-alignment.
²WHEEL 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 un-
Fig. 1 Wheel Alignment Measurements
JFRONT SUSPENSION AND AXLE 2 - 5
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
MODEL 35 AXLE
INDEX
page page
Axle Shaft............................... 16
Axle Shaft Seal and Bearing................. 17
Backlash and Contact Pattern Analysis......... 27
Cleaning/Inspection........................ 20
Differential Assembly....................... 21
Differential Disassembly.................... 18
Differential Measurement and Installation........ 25
Differential Removal....................... 18
Drive Axle Assembly ReplacementÐXJ Vehicles . . 14Drive Axle Assembly ReplacementÐYJ Vehicles . . 14
Final Assembly........................... 29
General Information....................... 13
Lubricant Change......................... 13
Lubricant Specifications..................... 13
Pinion Gear Depth Information............... 21
Pinion Measurement and Assembly............ 22
Pinion Removal/Disassembly................. 19
Pinion Shaft Seal Replacement............... 15
GENERAL INFORMATION
The Model 35 housing has 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 below the centerline
of the ring gear.
The axle has a vent hose to relieve internal pres-
sure caused by lubricant vaporization and internal
expansion.
The axles are equipped with semi-floating axle
shafts, meaning that loads are supported by the axle
shaft and bearings. The axle shafts are retained by
C-clips in the differential side gears.
The cover provides a means for servicing the differ-
ential without removing the axle.
Axles may be equipped with drum or disc brakes.
The axles that are equipped with ABS brake have a
tone ring pressed on the axle shaft. Use care when
removing axle shafts as NOT to damage the tone
wheel or the sensor.
The Model 35 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
threaded roll pin. Differential bearing preload and
ring gear backlash is adjusted by the use of spacer
shims. Pinion bearing preload is set and maintained
by the use of a collapsible spacer.
For complete drive axle assembly removal
and installation refer to Drive Axle Assembly
Replacement in this Group.
LUBRICANT SPECIFICATIONS
Multi-purpose, hypoid gear lubricant should be
used for Model 35 axle. The lubricant should haveMIL-L-2105C and API GL 5 quality specifications.
MOPAR Hypoid Gear Lubricant conforms to both of
these specifications.
²Lubricant for Model 35 axle is a thermally stable
SAE 80W-90 gear lubricant.
²Lubricant for Model 35 axle with Trailer Tow is
SAE 75W-140 SYNTHETIC gear lubricant.
²Trac-Lok differentials add 4 oz. of friction modifier.
²Lubricant quantity is 1.66 L (3.50 pts.).
Refer to Group 0, Lubrication and Maintenance for
additional information.
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.
(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 to 41 Nzm (30 ft. lbs.) torque.
(8) Refill differential with Mopar Hypoid Gear Lu-
bricant to bottom of the fill plug hole.
JREAR SUSPENSION AND AXLES 3 - 13
LUBRICANT SPECIFICATIONS
Multi-purpose, hypoid gear lubricant should be
used in the 8 1/4 inch axle. The lubricant should
have MIL-L-2105C and API GL 5 quality specifica-
tions. MOPARtHypoid Gear Lubricant conforms to
both of these specifications.
²The factory installed lubricant for the 8 1/4 inch
rear axle is SAE 80W 90 gear lubricant.
²The factory installed lubricant quantity is 6762
fluid oz.
CAUTION: Overfilling the differential can result in
lubricant foaming and overheating.
Refer to Group 0, Lubrication and Maintenance for
additional information.
CAUTION: If axle is submerged in water, lubricant
must be replaced immediately to avoid possible
premature axle failure.
DRIVE AXLE ASSEMBLY REPLACEMENTÐXJ
VEHICLES
REMOVAL
(1) Raise the vehicle. Position support stands un-
der the frame rails slightly in front the springs.
(2) Remove the rear wheels.
(3) Mark the drive shaft yoke and axle pinion yoke
for alignment reference. Disconnect the drive shaft
from the axle.
(4) Disconnect the axle vent hose.
(5) Disconnect the parking brake cables at the
equalizer or backing plate.
(6) Disconnect the shock absorbers from the axle
brackets.
(7) Disconnect the brake hose at the axle junction
block.Do not disconnect the wheel cylinder tub-
ing fittings.
(8) If equipped, disconnect ABS wiring connections
at the axle.
(9) Support the axle with a hydraulic jack under
the differential.
(10) Remove the spring U-bolts from the plate
brackets.
(11) 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 axle and align the spring center bolts
with the locating holes in the axle pads and plate
brackets.
(3) Install the spring U-bolts through the plate
brackets and tighten to 70 Nzm (52 ft. lbs.) torque.
(4) Install ABS wiring connections (if equipped) at
the axle.
(5) Connect the brake hose at the axle junction
block.
(6) Install the shock absorbers to the axle brackets
and tighten to 62 Nzm (46 ft. lbs.) torque.
(7) Connect the parking brake cables at the equal-
izer or backing plate.
(8) Connect the vent hose to the tube fitting.
(9) 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.
(10) Check differential lubricant and add if neces-
sary.
(11) Install the wheel and tire.
(12) Bleed the brakes.
(13) Remove the supports and lower the vehicle.
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. 2). 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.
(7) Install the cover and any identification tag.
Tighten the cover bolts in a criss-cross pattern to 47
Nzm (35 ft. lbs.) torque.
(8) Refill the differential with Mopar Hypoid Gear
Lubricant 13 mm (1/2 in.) below the fill plug hole.
With Trac-Lok differentials, add a container of Mopar
Hypoid Gear Lubricant Additive.
CAUTION: Overfilling the differential can result in
lubricant foaming and overheating.
(9) Install the fill hole plug and lower the vehicle.
JREAR SUSPENSION AND AXLES 3 - 31
TRAC-LOK DIFFERENTIAL
OPERATION
In a conventional differential, the torque applied to
the ring gear is transmitted to the axle shafts through
the differential gears. During normal operation, the
torque transmitted to each wheel is equal at all times.
However, if one wheel spins, the opposite wheel will
generate only as much torque as the spinning wheel.
In the Trac-Lok differential, part of the ring gear
torque is transmitted through clutch packs. The clutch
packs contain multiple disc. The clutch will have radial
grooves on the plates, and concentric grooves on the
discs or bonded fiber material which is smooth.
In operation, the Trac-Lok clutches are engaged by
two concurrent forces. The first being preload force ex-
erted through Belleville spring washers. The second is
from separating forces generated by the side gears (Fig.
1).
The Trac-Lok design provides the normal differential
action needed for turning corners. It also provides for
the transmission of equal torque to both wheels when
driving straight ahead. When one wheel loses traction,
the clutch packs transfer torque to the wheel having the
most traction. Trac-lok differentials resist wheel spin on
bumpy roads. It also provides more pulling power when
one wheel loses traction. Pulling power is continuous
until both wheels lose traction. If both wheels slip due
to unequal traction, Trac-Lok operation is normal. In ex-
treme cases of differences of traction, the wheel with
the least traction may spin. This occurs after the Trac-
Lok has transferred as much torque as possible to the
non-spinning wheel.
NOISE DIAGNOSIS
If chatter occurs when turning corners, the most
probable cause is incorrect or contaminated lubri-
cant. Before removing the Trac-Lok unit for repair,
drain, flush and refill the axle with the specified lu-
bricant. Refer to Lubricant change in this Group.
A container of Trac-Lok Lubricant (friction modi-
fier) should be added after.
Vehicles with a limited slip differential should be
road tested by making 10 to 12 slow figure-eight
turns. This maneuver will pump the lubricant
through the clutch discs.
Refer to Group 0, Lubrication and Maintenance for
additional information.
DIFFERENTIAL TEST
WARNING: WHEN SERVICING VEHICLES WITH A
LIMITED SLIP DIFFERENTIAL DO NOT USE THE EN-
GINE TO TURN THE AXLE AND WHEELS. BOTH
REAR WHEELS MUST BE RAISED AND THE VEHI-
CLE SUPPORTED. A LIMITED SLIP AXLE CAN EX-
ERT ENOUGH FORCE (IF ONE WHEEL IS IN
CONTACT WITH THE SURFACE) TO CAUSE THE
VEHICLE TO MOVE.
The differential can be tested without removing the
differential case by measuring rotating torque. Make
sure brakes are not dragging during this measure-
ment.
(1) Engine off, transmission in neutral, and park-
ing brake off.
(2) Place blocks in front and rear of both front
wheels.
(3) Jack up one rear wheel until it is completely off
the ground.
(4) Remove wheel and bolt special tool to studs.
Fig. 1 Limited Slip Differential OperationÐBoth
Wheels Driving
JREAR SUSPENSION AND AXLES 3 - 45