front pinion JEEP LIBERTY 2002 KJ / 1.G Owner's Manual

(6) Position Spreader W-129-B onto the differential
locating holes and install the safety holddown clamps
(Fig. 38). Tighten the tool turnbuckle finger-tight.
(7) Install a Pilot Stud C-3288-B at the left side of
the differential housing. Attach Dial Indicator C-3339
to pilot stud. Load indicator plunger against the
opposite side of the housing and zero the indicator.
(8) Spread the housing to remove the differential
case from the housing. Measure the distance with the
dial indicator (Fig. 39).
CAUTION: Never spread the differential housing
over 0.34 mm (0.013 in). If housing is over-spread, it
could be distorted or damaged.
(9) Remove the dial indicator.
(10) Holding the differential case in position, and
remove bearing cap bolts and caps.
(11) Remove the differential from the housing (Fig.
40). Ensure differential bearing cups and shims
remain in position on the differential bearings.(12) Tag differential bearing cups and shims to
indicate their location.
(13) Remove spreader from housing.
DISASSEMBLY
(1) Remove ring gear.
(2) Remove roll-pin holding mate shaft in housing.
(3) Remove pinion gear mate shaft.
(4) Rotate differential side gears and remove the
pinion mate gears and thrust washers (Fig. 41).
(5) Remove differential side gears and thrust
washers.
ASSEMBLY
(1) Install differential side gears and thrust wash-
ers.
(2) Install pinion mate gears and thrust washers.
(3) Install pinion gear mate shaft.
(4) Align hole in the pinion gear mate shaft with
the hole in the differential case.
Fig. 38 DIFFERENTIAL SPREADER
1 - DIFFERENTIAL HOUSING
2 - SAFETY CLAMPS
3 - SPREADER
4 - TURNBUCKLE
Fig. 39 SPREAD DIFFERENTIAL CASE
1 - PILOT STUD
2 - DIAL INDICATOR
3 - SPREADER
KJFRONT AXLE - 186FIA 3 - 41
DIFFERENTIAL (Continued)

(5) Install the roll-pin in the differential case with
a hammer and punch (Fig. 42). Peen the edge of the
roll-pin hole in the differential case in two places
180É apart.
(6) Lubricate all differential components with
hypoid gear lubricant.
(7) Install ring gear.
INSTALLATION
NOTE: If differential bearings or differential case are
replaced, Refer to adjustments fore Differential
Bearing Preload and Gear Backlash procedures.
(1) Position Spreader W-129-B on differential loca-
tion holes and install safety holddown clamps.
Tighten the tool turnbuckle finger-tight.
(2) Install Pilot Stud C-3288-B to the left side of
the differential housing. Attach Dial Indicator C-3339
to pilot stud. Load the indicator plunger against the
opposite side of the housing and zero the indicator.
(3) Spread the housing to install the differential
case and preload shims in the housing. Measure the
distance with the dial indicator.
CAUTION: Never spread the differential housing
over 0.34 mm (0.013 in). If housing is over-spread, it
could be distorted or damaged.
Fig. 40 DIFFERENTIAL CASE
1 - DIFFERENTIAL HOUSING
2 - DIFFERENTIAL CASE
3 - DIFFERENTIAL BEARINGS
Fig. 41 PINION MATE GEAR
1 - THRUST WASHER
2 - SIDE GEAR
3 - PINION MATE GEAR
Fig. 42 PINION MATE SHAFT ROLL-PIN
1 - PUNCH
2 - PINION MATE SHAFT
3 - MATE SHAFT LOCKPIN
3 - 42 FRONT AXLE - 186FIAKJ
DIFFERENTIAL (Continued)

INSTALLATION
(1) Install differential case bearings with Installer
C-3716-A and Handle C-4171 (Fig. 45).
(2) Install differential into the housing.
PINION GEAR/RING GEAR
REMOVAL
NOTE: The ring gear and pinion are serviced as a
matched set. Never replace ring gear without
replacing the matched pinion gear.
(1) Raise and support vehicle
(2) Mark pinion companion flange and propeller
shaft for installation alignment.
(3) Remove propeller shaft from pinion companion
flange and tie propeller shaft to underbody.
(4) Remove axle assembly from the vehicle.
(5) Remove differential from axle housing.
(6) Place differential case in a vise with soft metal
jaw (Fig. 46).
(7) Remove bolts holding ring gear to differential
case.
(8) Driver ring gear off the differential case with a
rawhide hammer (Fig. 46).(9) With Spanner Wrench 6958 and a short length
of 1 in. pipe, hold pinion companion flange and
remove pinion nut (Fig. 47).
Fig. 45 DIFFERENTIAL CASE BEARINGS
1 - HANDLE
2 - DIFFERENTIAL
3 - BEARING
4 - INSTALLER
Fig. 46 RING GEAR
1 - DIFFERENTIAL CASE
2 - RING GEAR
3 - HAMMER
Fig. 47 PINION COMPANION FLANGE
1 - SPANNER WRENCH
2 - PINION COMPANION FLANGE
3 - 44 FRONT AXLE - 186FIAKJ
DIFFERENTIAL CASE BEARINGS (Continued)

(10) Remove pinion companion flange from pinion
shaft with Remover C-452 and Flange Wrench
C-3281 (Fig. 48).
(11) Remove pinion gear and collapsible spacer
from housing (Fig. 49).(12) Remove front pinion bearing cup, bearing, oil
slinger and pinion seal with Remover C-149 and
Handle C-4171 (Fig. 50).
(13) Remove rear pinion bearing cup (Fig. 51) with
Remover C-4307 and Handle C-4171.
Fig. 48 PINION FLANGE REMOVER
1 - SPANNER WRENCH
2 - REMOVER
Fig. 49 PINION GEAR
1 - RAWHIDE HAMMER
Fig. 50 FRONT BPINION BEARING CUP
1 - REMOVER
2 - HANDLE
Fig. 51 REAR PINION BEARING CUP
1 - REMOVER
2 - HANDLE
KJFRONT AXLE - 186FIA 3 - 45
PINION GEAR/RING GEAR (Continued)

(14) Remove collapsible preload spacer from pinion
gear (Fig. 52).
(15) Remove rear pinion bearing from the pinion
with Puller/Press C-293-PA and Adapters C-293-39
(Fig. 53). Remove oil slinger/pinion depth shim from
the pinion shaft and record thickness.
INSTALLATION
NOTE: Pinion depth shims are placed between the
rear pinion bearing and the pinion gear head to
achieve proper ring and pinion gear mesh. If ring
and pinion gears are reused, the pinion oil slinger/
depth shim should not require replacement. Refer
to Adujstments (Pinion Gear Depth) to select the
proper thickness shim before installing pinion gear.
(1) Apply Mopar Door Ease or equivalent lubricant
to outside surface of pinion bearing cups.
(2) Install rear bearing cup with Installer C-4308
and Handle C-4171 and verify cup is seated.
(3) Install front bearing cup with Installer D-146
and Handle C-4171 (Fig. 54) and verify cup is seated.
(4) Install front pinion bearing, and oil slinger if
equipped.
Fig. 52 COLLAPSIBLE PRELOAD SPACER
1 - COLLAPSIBLE SPACER
2 - SHOULDER
3 - PINION GEAR
4 - OIL SLINGER
5 - REAR BEARING
Fig. 53 REAR PINION BEARING
1 - PULLER
2 - VISE
3 - ADAPTERS
4 - PINION GEAR SHAFT
Fig. 54 FRONT PINION BEARING CUP
1 - INSTALLER
2 - HANDLE
3 - 46 FRONT AXLE - 186FIAKJ
PINION GEAR/RING GEAR (Continued)

(5) Apply a light coating of gear lubricant on the
lip of pinion seal and intall seal with an appropriate
installer (Fig. 55).
(6) Install rear pinion bearing and oil slinger/depth
shim onto the pinion shaft with Installer 6448 and a
press (Fig. 56).(7) Install anewcollapsible spacer on pinion shaft
and install the pinion into the housing (Fig. 57).
(8) Install pinion companion flange, with Installer
W-162-D, Cup 8109 and Spanner Wrench 6958.
(9) Install pinion anewnut onto the pinion gear
and tighten the nut to 216 N´m (160 ft. lbs.).Do not
over-tighten.
CAUTION: Never loosen pinion gear nut to decrease
pinion rotating torque and never exceed specified
preload torque. If preload torque is exceeded a new
collapsible spacer must be installed.
Fig. 55 PINION SEAL
1 - HANDLE
2 - INSTALLER
Fig. 56 REAR PINION BEARING
1 - INSTALLER
2 - OIL SLINGER
3 - PINION GEAR
4 - REAR PINION BEARING
5 - PRESS
Fig. 57 COLLAPSIBLE PRELOAD SPACER
1 - COLLAPSIBLE SPACER
2 - SHOULDER
3 - PINION GEAR
4 - OIL SLINGER
5 - REAR BEARING
KJFRONT AXLE - 186FIA 3 - 47
PINION GEAR/RING GEAR (Continued)

(10) Use Flange Wrench 6958, a length of 1 in.
pipe and a torque wrench set at 678 N´m (500 ft. lbs.)
and crush collapsible spacer until bearing end play is
taken up (Fig. 58).
(11) Slowly tighten the nut in 6.8 N´m (5 ft. lb.)
increments until the required rotating torque is
achieved. Measure the rotating torque frequently to
avoid over crushing the collapsible spacer (Fig. 59).
(12) Rotate the pinion a minimum of ten times.
Verify pinion rotates smoothly and check rotating
torque with an inch pound torque wrench (Fig. 59).
Pinion gear rotating torque is:
²Original Bearings: 1 to 2.25 N´m (10 to 20 in.
lbs.).
²New Bearings: 1.69 to 2.82 N´m (15 to 25 in.
lbs.).
(13) Invert the differential case and start two ring
gear bolts. This will provide case-to-ring gear bolt
hole alignment.
(14) Invert the differential case in the vise. Install
newring gear bolts and alternately tighten to 108
N´m (80 ft. lbs.) (Fig. 60).
CAUTION: Never reuse the ring gear bolts. The
bolts can fracture causing extensive damage.
(15) Install differential in housing and verify dif-
ferential bearing preload, gear mesh and contact pat-
tern. Refer to Adjustment for procedure.
(16) Install differential cover and fill with gear
lubricant.
(17) Install propeller shaft with reference marks
aligned.
(18) Remove supports and lower vehicle.
Fig. 58 PINION FLANGE NUT
1 - SPANNER WRENCH
2 - PINION COMPANION FLANGE
Fig. 59 PINION ROTATING TORQUE
1 - PINION COMPANION FLANGE
2 - TORQUE WRENCH
Fig. 60 RING GEAR BOLTS
1 - TORQUE WRENCH
2 - RING GEAR BOLTS
3 - RING GEAR
4 - DIFFERENTIAL CASE
3 - 48 FRONT AXLE - 186FIAKJ
PINION GEAR/RING GEAR (Continued)

The Trac-lokŸ design provides the differential
action needed for turning corners and for driving
straight ahead during periods of unequal traction.
When one wheel looses traction, the clutch packs
transfer additional torque to the wheel having the
most traction. Trac-lokŸ differentials resist wheel
spin on bumpy roads and provide more pulling power
when one wheel looses traction. Pulling power is pro-
vided continuously until both wheels loose traction. If
both wheels slip due to unequal traction, Trac-lokŸ
operation is normal. In extreme cases of differences
of traction, the wheel with the least traction may
spin.
DIAGNOSIS AND TESTING - AXLE
GEAR NOISE
Axle gear noise can be caused by insufficient lubri-
cant, incorrect backlash, incorrect pinion depth, tooth
contact, worn/damaged gears, or the carrier housing
not having the proper offset and squareness.
Gear noise usually happens at a specific speed
range. The noise can also occur during a specific type
of driving condition. These conditions are accelera-
tion, deceleration, coast, or constant load.
When road testing, first warm-up the axle fluid by
driving the vehicle at least 5 miles and then acceler-
ate 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:
²Check for insufficient lubricant.
²Incorrect ring gear backlash.
²Gear damage.
Differential side gears and pinions can be checked
by turning the vehicle. They usually do not cause
noise during straight-ahead driving when the gears
are unloaded. The side gears are loaded during vehi-
cle turns. A worn pinion shaft can also cause a snap-
ping or a knocking noise.
BEARING NOISE
The axle shaft, differential and pinion bearings can
all produce noise when worn or damaged. Bearing
noise can be either a whining, or a growling sound.
Pinion bearings have a constant-pitch noise. This
noise changes only with vehicle speed. Pinion bearing
noise will be higher pitched because it rotates at a
faster rate. Drive the vehicle and load the differen-
tial. If bearing noise occurs, the rear pinion bearing
is the source of the noise. If the bearing noise is
heard during a coast, the front pinion bearing is the
source.
Worn or damaged differential bearings usually pro-
duce a low pitch noise. Differential bearing noise is
similar to pinion bearing noise. The pitch of differen-tial 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.
This will load the bearings and change the noise
level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.
LOW SPEED KNOCK
Low speed knock is generally caused by a worn
U-joint or by worn side±gear thrust washers. A worn
pinion shaft bore will also cause low speed knock.
VIBRATION
Vibration at the rear of the vehicle is usually
caused by a:
²Damaged drive shaft.
²Missing drive shaft balance weight(s).
²Worn or out-of-balance wheels.
²Loose wheel lug nuts.
²Worn U-joint(s).
²Loose/broken springs.
²Damaged axle shaft bearing(s).
²Loose pinion gear nut.
²Excessive pinion yoke run out.
²Bent axle shaft(s).
Check for loose or damaged front-end components
or engine/transmission mounts. These components
can contribute to what appears to be a rearend vibra-
tion. Do not overlook engine accessories, brackets
and drive belts.
NOTE: All driveline components should be exam-
ined before starting any repair.
DRIVELINE SNAP
A snap or clunk noise when the vehicle is shifted
into gear (or the clutch engaged), can be caused by:
²High engine idle speed.
²Transmission shift operation.
²Loose engine/transmission/transfer case mounts.
²Worn U-joints.
²Loose spring mounts.
²Loose pinion gear nut and yoke.
²Excessive ring gear backlash.
²Excessive side gear to case clearance.
The source of a snap or a clunk noise can be deter-
mined with the assistance of a helper. Raise the vehi-
cle on a hoist with the wheels free to rotate. Instruct
the helper to shift the transmission into gear. Listen
for the noise, a mechanics stethoscope is helpful in
isolating the source of a noise.
KJREAR AXLE - 198RBI 3 - 51
REAR AXLE - 198RBI (Continued)

PINION GEAR DEPTH VARIANCE
Original Pinion
Gear Depth
VarianceReplacement Pinion Gear Depth Variance
24232221 0 +1 +2 +3 +4
+4+0.008 +0.007 +0.006 +0.005 +0.004 +0.003 +0.002 +0.001 0
+3+0.007 +0.006 +0.005 +0.004 +0.003 +0.002 +0.001 020.001
+2+0.006 +0.005 +0.004 +0.003 +0.002 +0.001 020.00120.002
+1+0.005 +0.004 +0.003 +0.002 +0.001 020.00120.00220.003
0+0.004 +0.003 +0.002 +0.001 020.00120.00220.00320.004
21+0.003 +0.002 +0.001 020.00120.00220.00320.00420.005
22+0.002 +0.001 020.00120.00220.00320.00420.00520.006
23+0.001 020.00120.00220.00320.00420.00520.00620.007
24020.00120.00220.00320.00420.00520.00620.00720.008
PINION DEPTH MEASUREMENT
Measurements are taken with pinion cups and pin-
ion bearings installed in the housing. Take measure-
ments with a Pinion Gauge Set, Pinion Block 6735,
Arbor Discs 6732 and Dial Indicator C-3339 (Fig. 11).
(1) Assemble Pinion Height Block 6739, PinionBlock 6735 and rear pinion bearing onto Screw 6741
(Fig. 11).
(2) Insert assembled height gauge components,
rear bearing and screw into the housing through pin-
ion bearing cups (Fig. 12).
(3) Install front pinion bearing and Cone 6740
hand tight.
(4) Place Arbor Disc 6732 on Arbor D-115-3 in posi-
tion in the housing side bearing cradles (Fig. 13).
Install differential bearing caps on Arbor Discs and
tighten cap bolts. Refer to the Torque Specifications.
NOTE: Arbor Discs 6732 have different step diame-
ters to fit other axle sizes. Pick correct size step for
axle being serviced.
Fig. 11 PINION DEPTH TOOLS
1 - DIAL INDICATOR
2 - ARBOR
3 - PINION HEIGHT BLOCK
4 - CONE
5 - SCREW
6 - PINION BLOCK
7 - SCOOTER BLOCK
8 - ARBOR DISC
Fig. 12 PINION HEIGHT BLOCK
1 - PINION BLOCK
2 - PINION HEIGHT BLOCK
3 - 56 REAR AXLE - 198RBIKJ
REAR AXLE - 198RBI (Continued)

(8) Fill differential with gear lubricant.
(9) Install the brake drums
(10) Install wheel and tire assemblies.
(11) Lower the vehicle.
COLLAPSIBLE SPACER
REMOVAL
(1) Raise and support the vehicle.
(2) Remove wheel and tire assemblies.
(3) Remove rear brake drums.
(4) Mark the propeller shaft and pinion yoke for
installation reference.
(5) Remove the propeller shaft from the yoke.
(6) Rotate the pinion gear three or four times.
(7) Measure and record torque to rotate the pinion
gear with an inch pound dial-type torque wrench.
(8) Hold pinion yoke with Spanner Wrench 6958
and remove pinion nut and washer.
(9) Remove the pinion yoke with Remover C-452
and Flange Wrench C-3281 (Fig. 38).
(10) Remove pinion shaft seal with a pry tool or a
slide hammer mounted screw.
(11) Remove front pinion bearing using a pair of
pick tools. Pull the bearing straight off the pinion
gear shaft. If the bearing becomes bound on the pin-
ion shaft, lightly tap the end of the pinion gear with
a rawhide/rubber hammer.
(12) Remove the collapsible spacer.
INSTALLATION
(1) Install anewcollapsible preload spacer on pin-
ion shaft.
(2) Install pinion front bearing.(3) Apply a light coating of gear lubricant on the
lip of pinion seal and install anewseal with an
appropriate installer (Fig. 39).
(4) Install yoke with Screw 8112, Cup 8109 and
Spanner Wrench 6958 (Fig. 40).
(5) Install yoke washer andnewnut on the pinion
gear. Tighten the nut to 271 N´m (200 ft. lbs.).
CAUTION: Never loosen pinion gear nut to decrease
pinion gear bearing rotating torque and never
exceed specified preload torque. If preload torque
or rotating torque is exceeded a new collapsible
spacer must be installed.
Fig. 38 PINION YOKE
1 - FLANGE WRENCH
2 - YOKE
3 - REMOVER
Fig. 39 PINION SEAL
1 - HANDLE
2 - INSTALLER
Fig. 40 PINION YOKE INSTALLER
1 - INSTALLER
2 - PINION YOKE
3 - WRENCH
3 - 70 REAR AXLE - 198RBIKJ
PINION SEAL (Continued)