2002 JEEP LIBERTY axle

shim thickness is measured. The overall shim thick-
ness is the total of the dial indicator reading and the
preload specification added together. The gear back-
lash measurement determines the thickness of the
shim used on the ring gear side of the differential
case. Subtract the gear backlash shim thickness from
the total overall shim thickness and select that
amount for the pinion gear side of the differential
(Fig. 13). Differential shim measurements are per-
formed with spreader W-129-B removed.
SHIM SELECTION
NOTE: It is difficult to salvage the differential side
bearings during the removal procedure. Install
replacement bearings if necessary.
(1) Remove differential side bearings from differ-
ential case.
(2) Install ring gear on differential case and
tighten bolts to specification.
(3) Install Dummy Bearings D-348 on differential
case.
(4) Install differential case in the housing.
(5) Record the thickness of Dummy Shims 8107.
Insert the shims between the dummy bearings and
the differential housing (Fig. 14).
Fig. 12 PINION DEPTH MEASUREMENT
1 - SCOOTER BLOCK
2 - ARBOR
3 - DIAL INDICATOR
Fig. 13 SHIM LOCATIONS
1 - PINION GEAR DEPTH SHIM/OIL SLINGER
2 - DIFFERENTIAL BEARING SHIM
3 - RING GEAR
4 - DIFFERENTIAL BEARING SHIM
5 - COLLAPSIBLE SPACER
Fig. 14 DUMMY SHIMS
1 - DUMMY SHIM
2 - DIFFERENTIAL HOUSING
3 - DIFFERENTIAL CASE
4 - DUMMY BEARINGS
3 - 28 FRONT AXLE - 186FIAKJ
FRONT AXLE - 186FIA (Continued)

(6) Install the bearing caps in their correct posi-
tions and snug the bolts (Fig. 15).
(7) With a dead-blow hammer, seat the differential
dummy bearings to each side of the axle housing
(Fig. 16) and (Fig. 17).(8) Thread Pilot Stud C-3288-B into rear cover bolt
hole below ring gear.
(9) Attach a Dial Indicator C-3339 to the Pilot
Stud. Position the dial indicator plunger on flat sur-
face between the ring gear bolts.
(10) Push and hold differential case to pinion gear
side of the housing and zero dial indicator (Fig. 18).
Fig. 15 BEARING CAP BOLTS
Fig. 16 SEAT DUMMY BEARINGS PINION SIDE
1 - HAMMER
2 - DIFFERENTIAL HOUSING
3 - DIFFERENTIAL
Fig. 17 SEAT DUMMY BEARING RING GEAR SIDE
1 - DIFFERENTAIL HOUSING
2 - HAMMER
3 - RING GEAR
Fig. 18 DIFFERENTIAL PINION GEAR SIDE
1 - PINION SIDE
2 - PILOT STUD
3 - DIAL INDICATOR
KJFRONT AXLE - 186FIA 3 - 29
FRONT AXLE - 186FIA (Continued)

(11) Push and hold differential case to ring gear
side of the housing and record dial indicator reading
(Fig. 19).
(12) Add 0.152 mm (0.006 in.) to the zero end play
total. This new total represents the thickness of
shims to compress or preload the new bearings when
the differential is installed.
(13) Rotate dial indicator out of the way on the
pilot stud.
(14) Remove differential case and dummy bearings
from the housing.
(15) Install the pinion gear in the housing. Install
the pinion yoke and establish the correct pinion
rotating torque.
(16) Install differential case and Dummy Bearings
D-348 in the housing.
(17) Install a single dummy shim in the ring gear
side. Install bearing caps and tighten bolts snug.
(18) Seat ring gear side dummy bearing (Fig. 17).
(19) Position the dial indicator plunger on a flat
surface between the ring gear bolt heads.
(20) Push and hold differential case toward pinion
gear and zero dial indicator (Fig. 20).
(21) Push and hold differential case to ring gear
side of the housing and record dial indicator reading
(Fig. 21). Add dummy shim thickness to this reading.
This will be the total shim thickness to achieve zero
backlash.
(22) Subtract 0.076 mm (0.003 in.) from the dial
indicator reading to compensate for backlash between
ring and pinion gears. This total is the thickness
shim required to achieve proper backlash.
(23) Subtract the backlash shim thickness from
the total preload shim thickness. The remainder is
the shim thickness required on the pinion side of the
axle housing.(24) Rotate dial indicator out of the way on pilot
stud.
(25) Remove differential case and dummy bearings
from the housing.
(26) Install side bearings and cups on differential
case.
(27) Install spreader W-129-B with Adapter Set
6987 on the housing and spread axle opening enough
to receive differential case.
CAUTION: Never spread the differential housing
over 0.34 mm (0.013 in.). If the housing is over-
spread, it could be distorted or damaged.
Fig. 19 DIFFERENTIAL RING GEAR SIDE
1 - DIAL INDICATOR
2 - DIFFERENTIAL HOUSING
Fig. 20 DIFFERENTIAL PINION GEAR SIDE
1 - DIAL INDICATOR
2 - PINION GEAR
3 - RING GEAR
Fig. 21 DIFFERENTIAL RING GEAR SIDE
1 - DIAL INDICATOR
2 - PINION GEAR
3 - RING GEAR
3 - 30 FRONT AXLE - 186FIAKJ
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)

Fig. 24 GEAR TOOTH CONTACT PATTERNS
3 - 32 FRONT AXLE - 186FIAKJ
FRONT AXLE - 186FIA (Continued)

DIFFERENTIAL BEARING PRELOAD CHECK
The final check on the differential assembly before
installing the axles, is torque to rotate pinion and
differential combined. This will verify the correct dif-
ferential bearing preload.
Torque to rotate the differential and pinion is the
torque to rotate the pinion plus:Gear Ratio 3.73....0.45-0.75 N´m (3.9-6.6 in. lbs.)
Gear Ratio 3.91....0.43-0.72 N´m (3.8-6.4 in. lbs.)
Gear Ratio 4.10....0.41-0.69 N´m (3.6-6.0 in. lbs.)
SPECIFICATIONS - FRONT AXLE
SPECIFICATIONS
DESCRIPTION SPECIFICATION
Axle Ratio 3.73, 3.92, 4.10
Ring Gear Diameter 186 mm (7.33 in.)
Ring Gear Backlash 0.12-0.20 mm (0.005-0.008 in.)
Pinion Gear Standard Depth 92.1 mm (3.625 in.)
Pinion Bearing Preload 1.69-2.82 N´m (15-25 in. lbs.)
Differential Bearing Preload
Added To Pinion Torque To Rotate
Gear Ratio 3.73 0.45-0.75 N´m (3.9-6.6 in. lbs.)
Gear Ratio 3.92 0.43-0.72 N´m (3.8-6.4 in. lbs.)
Gear Ratio 4.10 0.41-0.69 N´m (3.6-6.0 in. lbs.)
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Ring Gear Bolts 95-122 70-90 -
Differential Bearing Cap
Bolts54-67 39-50 -
Differential Cover Bolts 19-26 14-19 -
Pinion Nut 217-352 160-260 -
Left Axle Bracket Bolts 61 45 -
Front Axle Bracket Bolts 61 45 -
Right Axle Bracket Bolts 88 65 -
Axle Brackets To Frame
Bolts88 65 -
KJFRONT AXLE - 186FIA 3 - 33
FRONT AXLE - 186FIA (Continued)

SPECIAL TOOLS
FRONT AXLE
PULLER C-293-PA
PLUG SP-3289
ADAPTER C-293-39
PULLER C-452
DIAL INDICATOR C-3339
INSTALLER C-3716-A
HANDLE C-4171
INSTALLER D-146
REMOVER D-149
INSTALLER W-162-D
3 - 34 FRONT AXLE - 186FIAKJ
FRONT AXLE - 186FIA (Continued)

CUP 8109
PINION DEPTH SET 6774
PINION BLOCK 8804
SPANNER WRENCH 6958
SPREADER W-129-B
ADAPTER KIT 6987B
PILOT STUD C-3288-B
REMOVER C-4307
INSTALLER C-4308
INSTALLER 6448
KJFRONT AXLE - 186FIA 3 - 35
FRONT AXLE - 186FIA (Continued)