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

AXLE SHAFTS
REMOVAL
(1) Place the transmission in Neutral.
(2) Raise and support vehicle.
(3) Remove right wheel and tire and assembly.
(4) Remove right half shaft from vehicle.
(5) Remove snap ring from axle shaft.
(6) Assemble Remover 8420A onto the shaft (Fig.
25). Thread slid hammer into remover and remove
shaft.
(7) Slide axle shaft out of the axle tube.
NOTE: Use care to prevent damage to axle shaft
bearing and seal, which will remain in axle shaft
tube.
INSTALLATION
(1) Lubricate bearing bore and seal lip with gear
lubricant. Insert axle shaft through seal, bearing
(Fig. 26) and engage it into side gear splines.
NOTE: Use care to prevent shaft splines from dam-
aging axle shaft seal.
(2) Push on the axle shaft until the axle shaft
snap-ring passes through the side gear.
(3) Install right half shaft.
(4) Install right wheel and tire assembly.
(5) Check differential fluid level.
(6) Lower vehicle.
AXLE SHAFT SEALS
REMOVAL
(1) Remove half shaft.
(2) Remove axle shaft for right side seal removal.
(3) Remove shaft seal with Remover 7794-A and a
slide hammer (Fig. 27).
Fig. 25 AXLE SHAFT PULLER
1 - SNAP RING GROVE
2 - SLID HAMMER THREADS
3 - REMOVER BLOCKS
4 - REMOVER COLLAR
Fig. 26 AXLE SHAFT SEAL
1 - BEARING
2 - SEAL
Fig. 27 SHAFT SEAL REMOVER
1 - SHAFT SEAL
2 - REMOVER
KJFRONT AXLE - 186FIA 3 - 37

(4) Rotate pinion a minimum of ten time and ver-
ify pinion rotates smoothly. Rotate the pinion shaft
with an inch pound torque wrench. Rotating torque
should be equal to the reading recorded during
removal plus 0.56 N´m (5 in. lbs.) (Fig. 35).
(5) If the rotating torque is low, use Spanner
Wrench 6958 to hold the pinion companion flange
and tighten the pinion shaft nut in 6.8 N´m (5 ft.
lbs.) increments until proper rotating torque is
achieved.
CAUTION: If maximum tightening torque is reached
prior to reaching the required rotating torque, the
collapsible spacer may have been damaged.
Replace the collapsible spacer.
(6) Install propeller shaft with installation refer-
ence marks aligned.
(7) Fill differential with gear lubricant.
(8) Install brake rotors and calipers.
(9) Install wheel and tire assemblies.
(10) Lower the vehicle.
DIFFERENTIAL
REMOVAL
(1) Remove axle from the vehicle.
(2) Remove differential housing cover (Fig. 36).
(3) Push right axle shaft out of side gear (Fig. 37)
and remove the shaft.
(4) Mark differential bearing caps for installation
reference.
(5) Loosen the bearing cap bolts.
Fig. 35 PINION ROTATING TORQUE
1 - PINION COMPANION FLANGE
2 - TORQUE WRENCHFig. 36 DIFFERENTIAL COVER
1 - COVER
2 - VENT TUBE
Fig. 37 RIGHT SHAFT IN SIDE GEAR
1 - AXLE SHAFT
2 - SCREWDRIVER
3 - SIDE GEAR
3 - 40 FRONT AXLE - 186FIAKJ
PINION SEAL (Continued)

(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)

(4) Remove the dial indicator.
(5) Install differential case in the housing. Ensure
differential bearing cups remain on the bearings and
preload shims are seated in the housing. Tap differ-
ential case to ensure bearings cups are seated in the
housing.
(6) Install bearing caps to their original locations
and loosely install cap bolts.
(7) Remove differential housing spreader (Fig. 43).
(8) Tighten the bearing cap bolts in a criss-cross
pattern to 54-68 N´m (39-50 ft. lbs.).
(9) Install the right axle shaft.
(10) Apply a 6.38mm (1/4 in.) bead of red Mopar
Silicone Sealer or equivalent to the housing cover.
CAUTION: If cover is not installed within 3 to 5 min-
utes, the cover must be cleaned and new RTV
applied or adhesion quality will be compromised.
(11) Install differential housing cover and tighten
bolts in a criss-cross pattern to 19-26 N´m (14-19 ft.
lbs.).(12) Install axle assembly in vehicle.
(13) Fill differential with lubricant and install fill
plug.
DIFFERENTIAL CASE
BEARINGS
REMOVAL
(1) Remove differential from the housing.
(2) Remove bearings from the differential case
with Puller/Press C-293-PA, Adapters C-293-39 and
Plug SP-3289 (Fig. 44).
Fig. 43 DIFFERENTIAL SPREADER
1 - DIFFERENTIAL HOUSING
2 - SAFETY CLAMPS
3 - SPREADER
4 - TURNBUCKLE
Fig. 44 DIFFERENTIAL BEARING PULLER
1 - PULLER
2 - ADAPTERS
3 - BEARING
4 - DIFFERENTIAL
5 - PLUG
KJFRONT AXLE - 186FIA 3 - 43
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) 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)

REAR AXLE - 198RBI
TABLE OF CONTENTS
page page
REAR AXLE - 198RBI
DESCRIPTION.........................49
OPERATION...........................49
DIAGNOSIS AND TESTING - AXLE..........51
REMOVAL.............................54
INSTALLATION.........................54
ADJUSTMENTS
ADJUSTMENT........................55
SPECIFICATIONS - REAR AXLE............62
SPECIAL TOOLS
REAR AXLE..........................63
AXLE SHAFTS
REMOVAL.............................65
INSTALLATION.........................65
AXLE BEARING/SEAL
REMOVAL.............................66
INSTALLATION.........................67
PINION SEAL
REMOVAL.............................68INSTALLATION.........................68
COLLAPSIBLE SPACER
REMOVAL.............................70
INSTALLATION.........................70
DIFFERENTIAL
REMOVAL.............................71
INSTALLATION.........................73
DIFFERENTIAL - TRAC-LOK
DIAGNOSIS AND TESTING - TRAC-LOKT.....74
DISASSEMBLY.........................75
CLEANING............................77
INSPECTION..........................77
ASSEMBLY............................77
DIFFERENTIAL CASE BEARINGS
REMOVAL.............................79
INSTALLATION.........................79
PINION GEAR/RING GEAR/TONE RING
REMOVAL.............................79
INSTALLATION.........................82
REAR AXLE - 198RBI
DESCRIPTION
The Rear Beam-design Iron (RBI) axle 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 axles are
equipped with semi±floating axle shafts, meaning
that loads are supported by the axle shaft and bear-
ings. The axle shafts are retained by the unit bear-
ing, retainer plate and bolts.
The integral type, hypoid gear design, housing has
the centerline of the pinion set below the centerline
of the ring gear. The differential case is a one-piece
design. The differential pinion mate shaft is retained
with a threaded screw. Differential bearing preload
and ring gear backlash is adjusted by the use of
selective spacer shims. Pinion bearing preload is set
and maintained by the use of a collapsible spacer
(Fig. 1).
The cover provides a means for servicing the differ-
ential without removing the axle. The axle has a vent
hose to relieve internal pressure caused by lubricant
vaporization and internal expansion.
Axles equipped with a Trac-Loktdifferential are
optional. A Trac-Loktdifferential has a one-piece dif-ferential case, and the same internal components as
a standard differential, plus two clutch disc packs.
OPERATION
The axle receives power from the transmission/
transfer case through the rear propeller shaft. The
Fig. 1 SHIM LOCATIONS
1 - PINION GEAR DEPTH SHIM
2 - DIFFERENTIAL BEARING SHIM-PINION GEAR SIDE
3 - RING GEAR
4 - DIFFERENTIAL BEARING SHIM-RING GEAR SIDE
5 - COLLAPSIBLE SPACER
KJREAR AXLE - 198RBI 3 - 49

rear propeller shaft is connected to the pinion gear
which rotates the differential through the gear mesh
with the ring gear bolted to the differential case. The
engine power is transmitted to the axle shafts
through the pinion mate and side gears. The side
gears are splined to the axle shafts.
STANDARD DIFFERENTIAL
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. 2).
When turning corners, the outside wheel must
travel a greater distance than the inside wheel 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
allows the axle shafts to turn at unequal speeds (Fig.
3). In this instance, the input torque applied to the
pinion gears is not divided equally. The pinion gears
now rotate 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.
TRAC-LOKŸ DIFFERENTIAL
The Trac-lokŸ clutches are engaged by two concur-
rent forces. The first being the preload force exerted
through Belleville spring washers within the clutch
packs. The second is the separating forces generated
by the side gears as torque is applied through the
ring gear (Fig. 4).
Fig. 2 DIFFERENTIAL-STRAIGHT AHEAD DRIVING
1 - IN STRAIGHT AHEAD DRIVING EACH WHEEL ROTATES AT
100% OF CASE SPEED
2 - PINION GEAR
3 - SIDE GEAR
4 - PINION GEARS ROTATE WITH CASE
Fig. 3 DIFFERENTIAL-ON TURNS
1 - PINION GEARS ROTATE ON PINION SHAFT
Fig. 4 TRAC-LOK DIFFERENTIAL
1 - CASE
2 - RING GEAR
3 - DRIVE PINION
4 - PINION GEAR
5 - MATE SHAFT
6 - CLUTCH PACK
7 - SIDE GEAR
8 - CLUTCH PACK
3 - 50 REAR AXLE - 198RBIKJ
REAR AXLE - 198RBI (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)