Bolts JEEP GRAND CHEROKEE 2003 WJ / 2.G Owner's Manual

DIFFERENTIAL
Differential side bearing preload and gear backlash
is achieved by selective shims positioned behind the
differential side bearing cones. The proper shim
thickness can be determined using slip-fit Dummy
Bearings D-348 in place of the differential side bear-
ings and a Dial Indicator C-3339. Before proceeding
with the differential bearing preload and gear back-
lash measurements, measure the pinion gear depth
and prepare the pinion for installation. Establishing
proper pinion gear depth is essential to establishing
gear backlash and tooth contact patterns. After the
overall shim thickness to take up differential side
play is measured, the pinion is installed, and the
gear backlash shim thickness is measured. The over-
all shim thickness is the total of the dial indicator
reading and the preload specification added together.
The gear backlash 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 dif-
ferential (Fig. 9). Differential shim measurements
are performed 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 side bearings D-348 on differen-
tial case.
(4) Install differential case in the housing.
CAUTION: When installing a Vari-LokTdifferential,
the oil feed tube must point to the bottom of the
housing. If differential is forced in with the oil feed
towards the top, the anti-rotation tabs will be dam-
aged.
(5) Record the thickness of Dummy Shims 8107.
Insert the shims between the dummy bearings and
the differential housing (Fig. 10).
Fig. 9 ADJUSTMENT SHIM LOCATIONS
1 - PINION DEPTH SHIM/OIL SLINGER
2 - DIFFERENTIAL BEARING SHIM
3 - RING GEAR
4 - DIFFERENTIAL BEARING SHIM
5 - COLLAPSIBLE SPACER
Fig. 10 DUMMY SHIM LOCATION
1 - DUMMY SHIM
2 - DIFFERENTIAL HOUSING
3 - DIFFERENTIAL CASE
4 - DUMMY BEARINGS
3 - 24 FRONT AXLE - 186FBIWJ
FRONT AXLE - 186FBI (Continued)

(6) Install the bearing caps in their correct posi-
tions and snug the bolts (Fig. 11).
(7) With a dead-blow hammer, seat the differential
dummy bearings to each side of the housing (Fig. 12)
and (Fig. 13).(8) Thread Pilot Stud C-3288-B into rear cover bolt
hole below ring gear (Fig. 14).
(9) Attach a dial indicator C-3339 to Pilot Stud.
Position the dial indicator plunger on a flat surface
between the ring gear bolt heads (Fig. 14).
Fig. 11 BEARING CAP BOLTS
1 - BEARING CAP
2 - DIFFERENTIAL HOUSING
3 - DIFFERENTIAL CASE
Fig. 12 SEAT DUMMY BEARING PINION SIDE
1 - HAMMER
2 - DIFFERENTIAL HOUSING
3 - DIFFERENTIAL CASE
Fig. 13 SEAT DUMMY BEARING RING GEAR SIDE
1 - DIFFERENTIAL HOUSING
2 - HAMMER
3 - DIFFERENTIAL CASE
Fig. 14 DIFFERENTIAL SIDE PLAY MEASUREMET
1 - DIFFERENTIAL CASE
2 - DIFFERENTIAL HOUSING
3 - PILOT STUD
4 - DIAL INDICATOR
WJFRONT AXLE - 186FBI 3 - 25
FRONT AXLE - 186FBI (Continued)

(10) Push and hold differential case to pinion gear
side of the housing and zero dial indicator (Fig. 15).
(11) Push and hold differential case to ring gear
side of the housing and record dial indicator reading
(Fig. 16).(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. 13).
(19) Position the dial indicator plunger on a flat
surface between the ring gear bolt heads (Fig. 14).
(20) Push and hold differential case toward pinion
gear and zero dial indicator (Fig. 17).
Fig. 15 ZERO DIAL INDICATOR
1 - FORCE DIFFERENTIAL CASE TO PINION GEAR SIDE
2 - PILOT STUD
3 - INDICATOR EXTENSION
4 - DIAL INDICATOR FACE
Fig. 16 RECORED DIAL INDICATOR READING
1 - DIAL INDICATOR
2 - DIFFERENTIAL CASE TO RING GEAR SIDE
3 - DIFFERENTIAL HOUSING
Fig. 17 ZERO DIAL INDICATOR
1 - DIAL INDICATOR
2 - FORCE DIFFERENTIAL CASE TO PINION GEAR SIDE
3 - PINION GEAR
4 - DIFFERENTIAL HOUSING
5 - DIFFERENTIAL CASE
3 - 26 FRONT AXLE - 186FBIWJ
FRONT AXLE - 186FBI (Continued)

DIFFERENTIAL BEARING PRELOAD CHECK
The final check on the differential assembly before
installing the axles is torque to rotate pinion and dif-
ferential combined. This will verify the correct differ-
ential bearing preload.Torque to rotate the differential and pinion should
be the torque to rotate the pinion plus 0.79-1.24 N´m
(7-11 in. lbs.).
SPECIFICATIONS
AXLE SPECIFICATIONS
DESCRIPTION SPECIFICATION
Axle Ratio 3.31, 3.55, 3.73, 3.91
Differential Side Gear Clearance 0.13-0.20 mm (0.005-0.008 in.)
Differential Bearing Preload 0.152 mm (0.006 in.)
Ring Gear Diameter 186 mm (7.33 in.)
Ring Gear Backlash 0.13-0.20 mm (0.005-0.008 in.)
Pinion Gear Std. Depth 92.08 mm (3.625 in.)
Pinion Bearing Preload - Original Bearings 1-2 N´m (10-20 in. lbs.)
Pinion Bearing Preload - New Bearings 1.7-3.4 N´m (15-30 in. lbs.)
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Fill Hole Plug 34 25 -
Differential Cover Bolts 41 30 -
Bearing Cap Bolts 61 45 -
Ring Gear Bolts 108 80 -
Axle Nut 237 175 -
Hub Bearing Bolts 102 75 -
3 - 30 FRONT AXLE - 186FBIWJ
FRONT AXLE - 186FBI (Continued)

AXLE SHAFTS
REMOVAL
If the axle shaft and hub bearing are being
removed in order to service another component, the
axle shaft and hub bearing can be removed as an
assembly.
(1) Raise and support the vehicle.
(2) Remove the wheel and tire assembly.
(3) Remove brake caliper, rotor and ABS wheel
speed sensor.
(4) Remove cotter pin, nut retainer and axle nut.
(5) Remove the hub bearing bolts (Fig. 22).
(6) Remove hub bearing and axle shaft assembly
(Fig. 23).Avoid damaging the axle shaft oil seals
in the axle housing.
(7) Remove brake rotor shield from the hub bear-
ing or knuckle.
INSTALLATION
(1) Thoroughly clean the axle shaft and apply a
thin film of Mopar Wheel Bearing Grease or equiva-
lent to the shaft splines, seal contact surface and hub
bore.
(2) Install brake rotor shield to the knuckle.
(3) Install hub bearing and axle shaft assembly or
axle shaft into the housing and differential side
gears. Avoid damaging the axle shaft oil seals in the
axle housing.
(4) Install the hub bearing.
(5) Install hub bearing bolts and tighten to 102
N´m (75 ft. lbs.).
(6) Install axle hub washer and nut and tighten
nut to 237 N´m (175 ft. lbs.). Install the nut retainer
and a new cotter pin.
(7) Install ABS wheel speed sensor, brake rotor
and caliper.
(8) Install the wheel and tire assembly.
(9) Remove support and lower the vehicle.
Fig. 22 HUB BEARING BOLTS
1 - AXLE SHAFT
2 - AXLE
3 - KNUCKLE
4 - HUB BEARING
Fig. 23 HUB BEARING AND AXLE ASSEMBLY
1 - AXLE
2 - KNUCKLE
3 - HUB BEARING
4 - AXLE SHAFT
3 - 34 FRONT AXLE - 186FBIWJ

²New Bearings: 1.7 to 3.4 N´m (15 to 30 in. lbs.).
(9) Install propeller shaft with reference marks
aligned.
(10) Install brake rotors and calipers.
(11) Add gear lubricant if necessary.
(12) Install wheel and tire assemblies.
(13) Lower vehicle.
DIFFERENTIAL
REMOVAL
(1) Raise and support the vehicle.
(2) Remove lubricant fill hole plug from the differ-
ential housing cover.
(3) Remove differential cover and drain lubricant.
(4) Clean the housing cavity with a flushing oil,
light engine oil or lint free cloth.Never use water,
steam, kerosene or gasoline for cleaning.
(5) Remove hub bearings and axle shafts.
(6) Note installation reference letters stamped on
the bearing caps and housing machined sealing sur-
face (Fig. 38).
(7) Loosen the differential bearing cap bolts.
(8) Position Spreader W-129-B with Adapter Kit
6987B on differential locating holes (Fig. 39). Install
hold down clamps and tighten the tool turnbuckle
finger-tight.
Fig. 37 PINION COMPANION FLANGE
1 - COMPANION FLNAGE
2 - DIFFERENTIAL HOUSING
3 - SPANNER WRENCH
Fig. 38 BEARING CAP IDENTIFICATION
1 - REFERENCE LETTERS
2 - REFERENCE LETTERS
Fig. 39 DIFFERENTIAL SPREADER LOCATION
1 - DIFFERENTIAL HOUSING
2 - ADAPTER
3 - HOLD DOWN CLAMPS
4 - SPREADER
5 - TURNBUCKLE
3 - 40 FRONT AXLE - 186FBIWJ
COLLAPSIBLE SPACER (Continued)

(9) Install a Pilot Stud C-3288-B at the left side of
the differential housing. Attach Dial Indicator C-3339
to stud. Load the lever adapter against the opposite
side of the housing (Fig. 40) and zero the indicator.
(10) Spread housing enough to remove the differ-
ential case from the housing. Measure the distance
with the dial indicator (Fig. 41).
CAUTION: Never spread the housing over 0.50 mm
(0.020 in). If housing is over-spread, it could dis-
torted and damaged the housing.
(11) Remove the dial indicator.
(12) Hold differential case in position and remove
differential bearing cap bolts and caps.
(13) Remove differential from the housing and tag
differential bearing cups to ensure location (Fig. 42).
(14) Remove differential case preload shims from
the axle housing.
(15) Remove spreader from housing. Tag differen-
tial bearing preload shims to ensure correct location.
Fig. 40 DIAL INDICATOR LOCATION
1 - CLAMP
2 - DIAL INDICATOR
3 - LEVER ADAPTER
4 - SPREADER
5 - PILOT STUDFig. 41 SPREAD DIFFERENTIAL HOUSING
1 - DIAL INDICATOR
2 - SPREADER
Fig. 42 DIFFERENTIAL CASE REMOVAL
1 - DIFFERENTIAL HOUSING
2 - DIFFERENTIAL CASE
3 - BEARING CUPS
WJFRONT AXLE - 186FBI 3 - 41
DIFFERENTIAL (Continued)

INSTALLATION
NOTE: If replacement differential bearings or differ-
ential case are being installed, differential side
bearing shim requirements may change. Refer to
Adjustments (Differential Bearing Preload and Gear
Backlash) to determine the proper shim selection.
(1) Position Spreader W-129-B with Adapter Kit
6987B on differential locating holes. Install hold
down clamps and tighten the tool turnbuckle finger-
tight.
(2) Install a Pilot Stud C-3288-B at 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 enough to install the case
in the housing. Measure the distance with the dial
indicator.
CAUTION: Never spread the housing over 0.50 mm
(0.020 in). If housing is over-spread, it could dis-
torted and damaged the housing.
(4) Remove the dial indicator.
(5) Install differential case in the housing (Fig.
46). Make sure the differential bearing cups remain
on the bearings and the preload shims remain
between the face of the bearing cup and housing. Tap
the differential case to ensure the bearings cups and
shims are fully seated in the housing.
CAUTION: On a Vari-lokTdifferential the oil feed
tube must be pointed at the bottom of the housing.
If differential is installed with the oil feed tube
pointed at the top, the anti-rotation tabs will be
damaged.
(6) Install the bearing caps at their original loca-
tions (Fig. 47).
(7) Loosely install differential bearing cap bolts.
(8) Remove axle housing spreader.
(9) Tighten the bearing cap bolts to 61 N´m (45 ft.
lbs.).
(10) Install the hub bearings and axle shafts.
Fig. 46 DIFFERENTIAL CASE REMOVAL
1 - DIFFERENTIAL HOUSING
2 - DIFFERENTIAL CASE
3 - BEARING CUPS
Fig. 47 Bearing Cap Reference
1 - REFERENCE LETTERS
2 - REFERENCE LETTERS
WJFRONT AXLE - 186FBI 3 - 43
DIFFERENTIAL (Continued)

(11) Apply a bead 6.35mm (1/4 inch) of red Mopar
Silicone Rubber Sealant or equivalent to the housing
cover (Fig. 48).
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.
(12) Install differential cover and tighten cover
bolts in a criss-cross pattern to 41 N´m (30 ft. lbs.).
(13) Fill differential with gear lubricant to bottom
of the fill plug hole.
(14) Tighten fill plug to 34 N´m (25 ft. lbs.).
(15) Remove support and lower the vehicle.
DIFFERENTIAL CASE
BEARINGS
REMOVAL
(1) Remove differential case from housing.
(2) Remove bearings from the differential case
with Puller C-293-PA, Adapters 8352 and Plug
SP-3289 (Fig. 49).
INSTALLATION
NOTE: If replacement differential side bearings or
differential case are being installed, differential side
bearing shim requirements may change. Refer to
Adjustments (Differential Bearing Preload and Gear
Backlash) to determine the proper shim selection.
CAUTION: Vari-lokTplenum must be fully seated
against the differential case prior to installing the
ring gear side differential bearing.
(1) Install differential side bearings with Handle
C-4171 and Installer C-3726-A (Fig. 50).
(2) Install differential in housing.
Fig. 48 DIFFERENTIAL COVER
1 - COVER
2 - SEALANT
3 - SEALANT BEADFig. 49 DIFFERENTIAL CASE BEARING
1 - ADAPTERS
2 - BEARING
3 - DIFFERENTIAL
4 - PLUG
5 - PULLER
3 - 44 FRONT AXLE - 186FBIWJ
DIFFERENTIAL (Continued)

PINION GEAR/RING GEAR
REMOVAL
NOTE: The ring gear and pinion are serviced as a
matched set. Nevar replace one gear without replac-
ing the other matching 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 differential from axle housing.
(5) Place differential case in a vise with soft metal
jaw (Fig. 51).
(6) Remove bolts holding ring gear to differential
case.
NOTE: On Veri-LokTdifferential the side bearing
and oil feed plenum must be removed before
removing the ring gear bolts.
(7) Driver ring gear off the differential case with a
rawhide hammer (Fig. 51).(8) With Spanner Wrench 6958 and a short length
of 1 in. pipe, hold pinion companion flange and
remove pinion nut and washer (Fig. 52).
(9) Remove pinion companion flange from pinion
shaft with Remover C-452 and Flange Wrench
C-3281.
Fig. 50 DIFFERENTIAL CASE BEARING
1 - INSTALLER
2 - HANDLE
Fig. 51 RING GEAR
1 - DIFFERENTIAL CASE
2 - RING GEAR
3 - HAMMER
Fig. 52 Pinion Flange
1 - PINION FLANGE
2 - FRONT AXLE
3 - SPANNER WRENCH
WJFRONT AXLE - 186FBI 3 - 45
DIFFERENTIAL CASE BEARINGS (Continued)