wheel torque JEEP XJ 1995 Service And User Guide

AXLE NOISE/VIBRATION DIAGNOSIS
INDEX
page page
Driveline Snap........................... 19
Gear and Bearing Noise.................... 18
General Information....................... 18Low Speed Knock......................... 19
Vibration................................ 19
GENERAL INFORMATION
Axle bearing problem conditions are usually caused
by:
²Insufficient or incorrect lubricant
²Foreign matter/water contamination
²Incorrect bearing preload torque adjustment
²Incorrect backlash (to tight)
When serviced, the bearings must be cleaned thor-
oughly. They should be dried with lint-free shop tow-
els.Never dry bearings with compressed air.
This will overheat them and brinell the bearing
surfaces. This will result in noisy operation af-
ter repair.
Axle gear problem conditions are usually the result
of:
²Insufficient lubrication
²Incorrect or contaminated lubricant
²Overloading (excessive engine torque) or exceeding
vehicle weight capacity
²Incorrect 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:
²Severe overloading
²Insufficient lubricant
²Incorrect lubricant
²Improperly tightened components
Overloading occurs when towing heavier than rec-
ommended loads. Component breakage can occur
when the wheels are spun excessively. Incorrect lu-
bricant quantity contributes to breakage. Loose dif-
ferential 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 re-
sult in bearing failure.
GEAR AND BEARING NOISE
GEAR NOISE
Axle gear noise can be caused by insufficient lubri-
cant. Incorrect backlash, tooth contact, or worn/dam-
aged 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 insuf-
ficient 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 dur-
ing 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 bear-
ings 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 differen-
tial. 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 pro-
duce 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.
2 - 18 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

(17) Tighten the track bar nut at the axle bracket
to 100 Nzm (74 ft. lbs.) torque.
(18) Check the front wheel alignment.
PINION SEAL REPLACEMENT
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) Remove the pinion yoke nut and washer. Use
Remover C-452 and Wrench C-3281 to remove the
pinion yoke (Fig. 2).
(6) Mark the positions of the yoke and pinion gear
for installation alignment reference.
(7) Use Remover 7794A and slide hammer to re-
move the pinion gear seal (Fig. 3).
INSTALLATION
(1) Apply a light coating of gear lubricant on the
lip of pinion seal. Install seal with Installer D-163
and Handle C-4171 (Fig. 4).
(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 to 217-352 Nzm (160-260 ft. lbs.) (Fig. 5).
(4) Align the installation reference marks and at-
tach the propeller shaft to the yoke.
(5) Add API grade GL 5 hypoid gear lubricant to
the differential housing, if necessary.
(6) Install wheel and tire assemblies.
(7) 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 mo-
tor 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 differen-
tial.
Fig. 2 Pinion Yoke Removal
Fig. 3 Seal Removal
Fig. 4 Pinion Seal Installation
JFRONT SUSPENSION AND AXLE 2 - 25

INSTALLATION
(1) Thoroughly clean the axle shaft (Fig. 6) and ap-
ply 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 dif-
ferential 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 SHAFTÐCARDAN U-JOINT
DISASSEMBLY
Single cardan U-joints are not serviceable. If defec-
tive, they must be replaced as a unit. If the bearings,
seals, spider or bearing caps are damaged or worn,
replace the complete U-joint.
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).
It can be helpful to saturate the bearing caps
with penetrating oil prior to removal.(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 di-
ameter than the bearing cap. Place the socket (driv-
er) against the opposite bearing cap. Position the
yoke with the sockets in a vise (Fig. 8).
(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.
Fig. 6 Hub, Knuckle and Axle Shaft
Fig. 7 Axle Shaft Outer U-Joint
2 - 26 FRONT SUSPENSION AND AXLEJ

AXLE SPECIFICATIONS
MODEL 30 FRONT AXLE
Axle Type........................................................Hypoid
Lubricant................SAE Thermally Stable 80W-90
Lube Capacity
YJ .....................................................1.65 L (3.76 pts.)
XJ .....................................................1.48 L (3.13 pts.)
Axle Ratio...................................3.07 3.55 3.73 4.10
DifferentialSide Gear Clearance .0.12-0.20mm (0.005-0.008 in.)
Ring Gear
Diameter .....................................18.09 cm (7.125 in.)
Backlash.........................0-0.15 mm (0.005-0.008 in.)
Pinion Std. Depth...................92.1 mm (3.625 in.)
Pinion Bearing Preload
Original Bearing ..................1-2 Nzm (10-20 in. lbs.)
New Bearing ......................1.5-4 Nzm (15-35 in. lbs.)
TORQUE SPECIFICATIONS
XJ FRONT SUSPENSION COMPONENTS
DESCRIPTION ................................................TORQUE
Shock Absorber
Upper Nut ......................................11 Nzm (8 ft. lbs.)
Lower Nut ....................................23 Nzm (17 ft. lbs.)
Suspension Arm Upper
Front Nut .....................................74 Nzm (55 ft. lbs.)
Rear Nut ......................................89 Nzm (66 ft. lbs.)
Suspension Arm Lower
Front and Rear Nut ..................115 Nzm (85 ft. lbs.)
Stabilizer Bar
Clamp Bolt ...................................54 Nzm (40 ft. lbs.)
Link Upper Nut ..........................36 Nzm (27 ft. lbs.)
Link Lower Nut ..........................95 Nzm (70 ft. lbs.)
Track Bar
Ball Stud Nut ..............................81 Nzm (60 ft. lbs.)
Axle Bracket Bolt ......................100 Nzm (74 ft. lbs.)
Track Bar Bracket
Bolts............................................125 Nzm (92 ft. lbs.)
Nut ..............................................100 Nzm (74 ft. lbs.)
Support Bolts ...............................42 Nzm (31 ft. lbs.)
YJ FRONT SUSPENSION COMPONENTS
DESCRIPTION ................................................TORQUE
Shock Absorber
Upper Nut ......................................13 Nzm (9 ft. lbs.)Lower Nut ....................................61 Nzm (45 ft. lbs.)
Stabilizer Bar
Clamp Bolt ...................................41 Nzm (30 ft. lbs.)
Link Nut ......................................61 Nzm (45 ft. lbs.)
Track Bar
Frame Bracket Nut.................142 Nzm (105 ft. lbs.)
Axle Bracket Nut ......................100 Nzm (74 ft. lbs.)
Spring
U-Bolt Nut .................................122 Nzm (90 ft. lbs.)
Front Shackle Bolt ..................135 Nzm (100 ft. lbs.)
Rear Pivot Bolt........................142 Nzm (105 ft. lbs.)
MODEL 30 AXLE
DESCRIPTION ................................................TORQUE
Fill Hole Plug...........................34 Nzm (25 ft. lbs.)
Diff. Cover Bolt........................41 Nzm (30 ft. lbs.)
Bearing Cap Bolt.....................61 Nzm (45 ft. lbs.)
Ring Gear Bolt.............95-122 Nzm (70-90 ft. lbs.)
Shift Motor Bolt.........................11 Nzm (8 ft. lbs.)
Axle Nut.................................237 Nzm (175 ft. lbs.)
Wheel Brg. Bolt......................102 Nzm (75 ft. lbs.)
Lower Ball Stud.....................108 Nzm (80 ft. lbs.)
Upper Ball Stud.....................101 Nzm (75 ft. lbs.)
ABS Sensor Bolt......................11 Nzm (96 in. lbs.)
JFRONT SUSPENSION AND AXLE 2 - 49

STANDARD DIFFERENTIAL OPERATION
The differential gear system divides the torque be-
tween the axle shafts. It allows the axle shafts to ro-
tate 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:
²The pinion gear rotates the ring gear²The ring gear (bolted to the differential case) ro-
tates the case
²The differential pinion gears (mounted on the pin-
ion mate shaft in the case) rotate the side gears
²The side gears (splined to the axle shafts) rotate
the shafts
During straight-ahead driving, the differential pin-
ion gears do not rotate on the pinion mate shaft. This
occurs because input torque applied to the 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. 3).
When turning corners, the outside wheel must travel
a greater distance than the inside wheel in order to
complete a turn. The difference must be compensated
for, to prevent the tires from scuffing and skidding
through turns. To accomplish this, the differential al-
lows the axle shafts to turn at unequal speeds (Fig. 4).
In this instance, the input torque applied to the pinion
gears is not divided equally. The pinion gears now ro-
tate 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.
Fig. 4 Differential OperationÐOn Turns
Fig. 1 Model 35 Differential Cover
Fig. 2 8 1/4 Differential Cover
Fig. 3 Differential OperationÐStraight-Ahead Driving
3 - 2 REAR SUSPENSION AND AXLESJ

SHOCK ABSORBER
REMOVAL
(1) Remove the shock absorber upper bolts from the
frame bracket (Fig. 1).
(2) Remove the lower attaching nut and washer
from the bracket stud. Remove the shock absorber.
INSTALLATION
(1) Install the shock absorber lower eye on the
spring bracket stud. Install the shock absorber and
upper bolts on the frame bracket (Fig. 1).
(2) Tighten the lower nut to 62 Nzm (46 ft. lbs.)
torque.
(3) Tighten the upper bolts to 23 Nzm (17 ft. lbs.)
torque.
LEAF SPRING
REMOVAL
(1) Raise vehicle at frame.
(2) Remove the wheel and tire assemblies.
(3) Support axle with hydraulic jack to relieve axle
weight.
(4) Disconnect the shock absorber from the axle
bracket or the spring bracket (Fig. 1).
(5) Disconnect the stabilizer bar link from the
spring bracket stud.(6) Remove nuts, U-bolts and spring bracket from
axle (Fig. 1).
(7) Remove nut and bolt attaching spring front eye
to shackle (Fig. 1).
(8) Remove nut and bolt from spring rear eye (Fig.
1).
(9) Remove spring from vehicle.
INSTALLATION
(1) Position the spring front eye in the bracket.
Loosely install the attaching bolt and nut (Fig. 1). Do
not tighten at this time.
(2) Position the rear eye in the shackle bracket.
Loosely install the attaching bolt and nut (Fig. 1). Do
not tighten at this time.
(3) Position the axle. Install the spring bracket,
U-bolts and nuts (Fig. 1). Tighten the nuts to 70 Nzm
(52 ft. lbs.) torque.
(4) Connect the stabilizer bar link to the spring
bracket.
(5) Connect the shock absorber to the axle bracket
or spring bracket.
(6) Remove the hydraulic jack.
(7) Lower the vehicle.
(8) Tighten the spring front eye attaching bolts to
148 Nzm (109 ft. lbs.) torque.
(9) Tighten the spring rear eye attaching bolts to
108 Nzm (80 ft. lbs.) torque.
Fig. 1 Spring & Shock AbsorberÐXJ Vehicles
3 - 4 REAR SUSPENSION AND AXLESJ

SHOCK ABSORBER
REMOVAL
(1) Remove the upper attaching nut and washer
from the frame bracket stud (Fig. 1).
(2) Remove the lower attaching nut, washers and
bolt from the axle bracket. Remove the shock ab-
sorber (Fig. 1).
INSTALLATION
(1) Position the shock upper eye on the frame
bracket stud. Install the washer and nut (Fig. 1).
(2) Position the shock lower eye in the axle shaft
tube bracket. Install the lower attaching bolt, wash-
ers and nut (Fig. 1).
(3) Tighten the upper and lower shock bolts to 61
Nzm (45 ft. lbs.) torque.
LEAF SPRING
REMOVAL
(1) Raise the vehicle at the frame.
(2) Use a hydraulic jack to relieve the axle weight.
(3) Remove the wheel and tire.
(4) Remove the nuts, the U-bolts and spring
bracket from the axle (Fig. 1).
(5) Remove the nut and bolt that attaches the
spring rear eye to the shackle (Fig. 1).
(6) Remove the nut and bolt from the spring front
eye (Fig. 1).
(7) Remove the spring from the vehicle.
INSTALLATION
(1) Position the spring front eye in the bracket.
Loosely install the attaching bolt and nut (Fig. 1). Do
not tighten at this time.
(2) Position the rear eye in the shackle bracket.
Loosely install the attaching bolt and nut (Fig. 1). Do
not tighten at this time.
(3) Align the rear spring center bolt with the locat-
ing hole in the rear axle spring pad.
(4) Lower the rear axle until it is completely sup-
ported by the spring.
Ensure that the spring center bolt is seated in
the axle spring pad locating hole. Realign the
center bolt with the locating hole, if necessary.
(5) Position the axle. Install the spring bracket, U-
bolts and nuts (Fig. 1). Tighten the U-bolt nuts to
122 Nzm (90 ft. lbs.) torque.
(6) Remove the hydraulic jack.
(7) Remove the support stands and lower the vehi-
cle.
(8) Tighten the spring shackle plate bolts and front
spring eye bolt to 135 Nzm (100 ft. lbs.) torque.
LEAF SPRING EYE BUSHING REPLACEMENT
(1) Assemble tools shown (Fig. 2). Tighten the nut
located at the socket wrench end of the threaded rod
until the bushing is forced out.
(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.
Fig. 1 Spring & Shock AbsorberÐYJ Vehicles
JREAR SUSPENSION AND AXLES 3 - 7

AXLE NOISE/VIBRATION DIAGNOSIS
INDEX
page page
Driveline Snap........................... 10
Gear and Bearing Noise..................... 9
General Information........................ 9
Limited Slip Differential..................... 10Low Speed Knock......................... 10
Rear Axle Alignment....................... 10
Vibration................................ 10
GENERAL INFORMATION
Axle bearing problem conditions are usually caused
by:
²Insufficient or incorrect lubricant
²Foreign matter/water contamination
²Incorrect bearing preload torque adjustment
²Incorrect backlash (to tight)
When serviced, the bearings must be cleaned thor-
oughly. They should be dried with lint-free shop tow-
els.Never dry bearings with compressed air.
This will overheat them and brinell the bearing
surfaces. This will result in noisy operation af-
ter repair.
Axle gear problem conditions are usually the result of:
²Insufficient lubrication
²Incorrect or contaminated lubricant
²Overloading (excessive engine torque) or exceeding
vehicle weight capacity
²Incorrect 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:
²Severe overloading
²Insufficient lubricant
²Incorrect lubricant
²Improperly tightened components
Overloading occurs when towing heavier than rec-
ommended loads. Component breakage can occur
when the wheels are spun excessively. Incorrect lu-
bricant quantity contributes to breakage. Loose dif-
ferential 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 re-
sult in bearing failure.
GEAR AND BEARING NOISE
GEAR NOISE
Axle gear noise can be caused by insufficient lubri-
cant. Incorrect backlash, tooth contact, or worn/dam-
aged 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 insuf-
ficient 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 dur-
ing 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 bear-
ings 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 differen-
tial. 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 pro-
duce 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.
JREAR SUSPENSION AND AXLES 3 - 9