2002 JEEP LIBERTY transfer case

SPECIFICATIONS
PROPELLER SHAFT
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Front Shaft - Companion
Flange Bolts30 22 -
Rear Shaft - Yoke Nuts 18 13 -
SPECIAL TOOLS
PROPELLER SHAFT - FRONT
REMOVAL
(1) Shift transmission and transfer case into Neu-
tral.
(2) Raise and support the vehicle.
(3) Mark companion flanges and C/V joints at the
front and rear of the propeller shaft for installation
reference.
(4) Remove bolts from the front and rear C/V
joints.
(5) Push propeller shaft forward to clear transfer
case companion flange (Fig. 8).
(6) Remove the shaft from the front axle compan-
ion flange.
(7) Tilt the front of the shaft down and pull shaft
forward and remove from the vehicle.
INSTALLATION
(1) Install propeller shaft between companion
flanges.
(2) Align marks on the companion flanges with the
marks on the C/V joints.
(3) Install front C/V joint bolts and tighten to 30
N´m (22 ft. lbs.).
(4) Install rear C/V joint bolts and tighten to 30
N´m (22 ft. lbs.).
(5) Lower vehicle.
Inclinometer 7663
Fig. 8 TRANSFER CASE COMPANION FLANGE
1 - FLANGE BOLT
2 - COMPANION FLANGE
3 - 6 PROPELLER SHAFTKJ
PROPELLER SHAFT (Continued)

PROPELLER SHAFT - REAR
REMOVAL
(1) Shift the transmission/transfer case into Neu-
tral.
(2) Raise and support vehicle.
(3) Mark a reference line across the pinion yoke
and propeller shaft for installation.
(4) Remove U-joint strap bolts at the pinion shaft
yoke.
(5) Pry open clamp holding the dust boot to propel-
ler shaft yoke (Fig. 9), if equipped.
(6) Slide slip yoke off of the transmission/transfer
case output shaft and remove the propeller shaft
(Fig. 10).
INSTALLATION
(1) Slide slip yoke on the transmission/transfer
case output shaft.
(2) Align reference marks on the pinion yoke and
propeller shaft.
(3) Install U-joint straps and tighten strap bolts to
18 N´m (13 ft. lbs.).
(4) Tighten dust boot clamp if equipped with
Clamp C-4975A (Fig. 11).
(5) Remove support and lower the vehicle.
Fig. 9 DUST BOOT CLAMP
1 - SLINGER
2 - BOOT
3-AWL
4 - TRANSFER CASE
Fig. 10 REAR PROPELLER SHAFT
1 - CLAMP
2 - YOKE
3 - PROPELLER SHAFT
4 - AXLE YOKE
5 - CLAMP
6 - OUTPUT SHAFT
7 - BOOT
Fig. 11 CRIMPING BOOT CLAMP
1 - CLAMP TOOL
2 - SLINGER
3 - BOOT
4 - CLAMPS
KJPROPELLER SHAFT 3 - 7

FRONT AXLE - 186FIA
TABLE OF CONTENTS
page page
FRONT AXLE - 186FIA
DESCRIPTION.........................19
OPERATION...........................19
DIAGNOSIS AND TESTING - AXLE..........20
REMOVAL.............................24
INSTALLATION.........................24
ADJUSTMENTS........................25
SPECIFICATIONS - FRONT AXLE...........33
SPECIAL TOOLS
FRONT AXLE........................34
AXLE SHAFTS
REMOVAL.............................37
INSTALLATION.........................37
AXLE SHAFT SEALS
REMOVAL.............................37
INSTALLATION.........................38
AXLE BEARINGS
REMOVAL.............................38INSTALLATION.........................38
PINION SEAL
REMOVAL.............................38
INSTALLATION.........................39
DIFFERENTIAL
REMOVAL.............................40
DISASSEMBLY.........................41
ASSEMBLY............................41
INSTALLATION.........................42
DIFFERENTIAL CASE BEARINGS
REMOVAL.............................43
INSTALLATION.........................44
PINION GEAR/RING GEAR
REMOVAL.............................44
INSTALLATION.........................46
FRONT AXLE - 186FIA
DESCRIPTION
The 186FIA (Model 30) axle consists of an alumu-
num center section with an axle tube extending from
one side. The tube is pressed into the differential
housing. The integral type housing, hypoid gear
design has the centerline of the pinion set below the
centerline of the ring gear.
The differential case is a one-piece design. The differ-
ential pinion mate shaft is retained with a roll-pin. Dif-
ferential bearing preload and ring gear backlash is
adjusted by the use of shims (select thickness). The
shims are located between the differential bearing cups
and the axle housing. Pinion bearing preload is set and
maintained by the use of a collapsible spacer.
The power is transferred from the axle through two
constant velocity (C/V) drive shafts to the wheel hubs.
The differential cover provides a means for inspec-
tion and service without removing the axle from the
vehicle. The cover has a vent tube used to relieve
internal pressure caused by vaporization and inter-
nal expansion.
OPERATION
The axle receives power from the transfer case through
the front propeller shaft. The front propeller shaft is con-
nected to the pinion gear which rotates the differential
through the gear mesh with the ring gear bolted to thedifferential 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.
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. 1).
Fig. 1 DIFFERENTIAL-STRAIGHT AHEAD DRIVING
1 - STRAIGHT AHEAD DRIVING
2 - PINION GEAR
3 - SIDE GEAR
4 - PINION GEARS ROTATE WITH CASE
KJFRONT AXLE - 186FIA 3 - 19

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.
DIAGNOSTIC CHART
Condition Possible Causes Correction
Wheel Noise 1. Wheel loose. 1. Tighten loose nuts.
2. Faulty, brinelled wheel bearing. 2. Replace bearing.
Axle Shaft Noise 1. Misaligned axle tube. 1. Inspect axle tube alignment.
Correct as necessary.
2. Bent or sprung axle shaft. 2. Inspect and correct as necessary.
3. End-play in pinion bearings. 3. Refer to pinion pre-load
information and correct as
necessary.
4. Excessive gear backlash
between the ring gear and pinion.4. Check adjustment of the ring
gear and pinion backlash. Correct
as necessary.
5. Improper adjustment of pinion
gear bearings.5. Adjust the pinion bearings
pre-load.
6. Loose pinion yoke nut. 6. Tighten the pinion yoke nut.
7. Scuffed gear tooth contact
surfaces.7. Inspect and replace as
necessary.
Axle Shaft Broke 1. Misaligned axle tube. 1. Replace the broken shaft after
correcting tube mis-alignment.
2 Vehicle overloaded. 2. Replace broken shaft and avoid
excessive weight on vehicle.
3. Erratic clutch operation. 3. Replace broken shaft and avoid
or correct erratic clutch operation.
4. Grabbing clutch. 4. Replace broken shaft and inspect
and repair clutch as necessary.
KJFRONT AXLE - 186FIA 3 - 21
FRONT AXLE - 186FIA (Continued)

(28) Place the bearing preload shims in the axle
housing, against the axle tubes.
(29) Install differential case into the housing.
(30) Remove spreader from the housing.
(31) Rotate the differential case several times to
seat the side bearings.
(32) Position the indicator plunger against a ring
gear tooth (Fig. 22).
(33) Push and hold ring gear upward while not
allowing the pinion gear to rotate.
(34) Zero dial indicator face to pointer.
(35) Push and hold ring gear downward while not
allowing the pinion gear to rotate. Dial indicator
reading should be between 0.12 mm (0.005 in.) and
0.20 mm (0.008 in.). If backlash is not within specifi-
cations transfer the necessary amount of shim thick-
ness from one side of the housing to the other (Fig.
23).
(36) Verify differential case and ring gear runout
by measuring ring to pinion gear backlash at eight
locations around the ring gear. Readings should not
vary more than 0.05 mm (0.002 in.). If readings vary
more than specified, the ring gear or the differential
case is defective.
After the proper backlash is achieved, perform
Gear Contact Pattern Analysis procedure.
GEAR CONTACT PATTERN
The ring gear and pinion teeth contact patterns
will show if the pinion depth is correct in the hous-
ing. It will also show if the ring gear backlash has
been adjusted correctly. The backlash can be adjusted
within specifications to achieve desired tooth contact
patterns.
(1) Apply a thin coat of hydrated ferric oxide or
equivalent to the drive and coast side of the ring gear
teeth.
(2) Wrap, twist and hold a shop towel around the
pinion yoke to increase the turning resistance of the
pinion. This will provide a more distinct contact pat-
tern.
(3) With a boxed end wrench on a ring gear bolt,
rotate the differential case one complete revolution in
both directions while a load is being applied from
shop towel.
The areas on the ring gear teeth with the greatest
degree of contact against the pinion teeth will squee-
gee the compound to the areas with the least amount
of contact. Note and compare patterns on the ring
gear teeth to Gear Tooth Contact Patterns chart (Fig.
24)and adjust pinion depth and gear backlash as nec-
essary.Fig. 22 RING GEAR BACKLASH
1 - DIAL INDICATOR
2 - RING GEAR
Fig. 23 BACKLASH SHIMS
KJFRONT AXLE - 186FIA 3 - 31
FRONT AXLE - 186FIA (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

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)

(24) Rotate dial indicator out of the way on pilot
stud.
(25) Remove differential case and dummy bearings
from the housing.
(26) Install new side bearing cones and cups on
differential case.
(27) Install spreader W-129-B and some compo-
nents of Adapter Set 6987 on differential housing and
spread axle opening enough to receive differential
case.
(28) Place side bearing shims into the housing
against the axle tubes.
(29) Install differential case in the housing.
(30) Rotate the differential case several times to
seat the side bearings.
(31) Position the indicator plunger against a ring
gear tooth (Fig. 22).
(32) Push and hold ring gear upward while not
allowing the pinion gear to rotate.
(33) Zero dial indicator face to pointer.
(34) Push and hold ring gear downward while not
allowing the pinion gear to rotate. Dial indicator
reading should be between 0.13-0.20 mm (0.005-0.008
in.). If backlash is not within specifications transfer
the necessary amount of shim thickness from one
side of the differential housing to the other (Fig. 23).
(35) Verify differential case and ring gear runout
by measuring ring to pinion gear backlash at eight
locations around the ring gear. Readings should not
vary more than 0.05 mm (0.002 in.). If readings varymore than specified, the ring gear or the differential
case is defective.
After the proper backlash is achieved, perform the
Gear Contact Pattern Analysis procedure.
GEAR CONTACT PATTERN
The ring gear and pinion teeth contact patterns
will show if the pinion depth is correct in the hous-
ing. It will also show if the ring gear backlash has
been adjusted correctly. The backlash can be adjusted
within specifications to achieve desired tooth contact
patterns.
(1) Apply a thin coat of hydrated ferric oxide or
equivalent to the drive and coast side of the ring gear
teeth.
(2) Wrap, twist, and hold a shop towel around the
pinion yoke to increase the turning resistance of the
pinion. This will provide a more distinct contact pat-
tern.
(3) With a boxed end wrench on a ring gear bolt,
rotate the differential case one complete revolution in
both directions while a load is being applied from
shop towel.
The areas on the ring gear teeth with the greatest
degree of contact against the pinion teeth will
squeeze the compound to the areas with the least
amount of contact. Note and compare patterns on the
ring gear teeth to Gear Tooth Contact Patterns chart
(Fig. 24) and adjust pinion depth and gear backlash
as necessary.
Fig. 22 RING GEAR BACKLASH
1 - DIAL INDICATOR
Fig. 23 BACKLASH SHIM
3 - 60 REAR AXLE - 198RBIKJ
REAR AXLE - 198RBI (Continued)