Page 127 of 2585
(5) Remove four overrunning clutch housing-to-dif-
ferential assembly bolts (Fig. 8) and remove housing.
(6) Remove front bearing snap ring (Fig. 14).
(7) Remove front bearing (Fig. 14).
(8) Remove o-ring and washer from overrunning
clutch assembly (Fig. 14).
(9) Remove overrunning clutch assembly from vis-
cous coupler (Fig. 9).(10) Remove viscous coupler from differential pin-
ion shaft (Fig. 10).
(11) Remove shim (select) from differential pinion
gear (Fig. 11).
Fig. 8 Overrunning Clutch Housing Bolts
1 - OVERRUNNING CLUTCH HOUSING
2 - BOLT (FOUR)
Fig. 9 Overrunning Clutch
1 - OVERRUNNING CLUTCH
2 - VISCOUS COUPLER
Fig. 10 Viscous Coupler
1 - VISCOUS COUPLER
2 - DIFFERENTIAL PINION
Fig. 11 Shim (Select)
1 - SHIM (SELECT)
2 - DIFFERENTIAL PINION
3 - 28 REAR DRIVELINE MODULERS
REAR DRIVELINE MODULE (Continued)
Page 128 of 2585
(12) Remove overrunning clutch housing large
o-ring from differential assembly (Fig. 14).
(13) Remove output flanges using suitable screw-
drivers and wood blocks to protect casting (Fig. 12).(14) Remove output flange seals (Fig. 13).
ASSEMBLY
(1) Install output flange seals using tools C4171
and 8493 (Fig. 15).
(2) Install large overrunning clutch housing o-ring
to differential assembly (Fig. 14).
(3) Install shim to differential pinion shaft (Fig.
16).
Fig. 12 Output Flange Removal
1 - WOOD BLOCK
2 - PRYBAR
3 - OUTPUT SHAFT
4 - PRYBAR
5 - WOOD BLOCK
6 - DIFFERENTIAL CASE
Fig. 13 Output Flange Seal Removal
1 - OUTPUT FLANGE SEAL
2 - SCREWDRIVER
RSREAR DRIVELINE MODULE3-29
REAR DRIVELINE MODULE (Continued)
Page 129 of 2585
Fig. 14 Drive Line Module
1 - NUT, INPUT FLANGE 6 - BEARING, FRONT 11 - VISCOUS COUPLER
2 - WASHER, INPUT FLANGE NUT 7 - SNAP RING, BEARING RETAINER 12 - O-RING, OVERRUNNING CLUTCH
HOUSING
3 - INPUT FLANGE/SHIELD 8 - O-RING 13 - SHIM (SELECT)
4 - SEAL, INPUT FLANGE 9 - WASHER 14 - DIFFERENTIAL ASSEMBLY
5 - OVERRUNNING CLUTCH HOUSING
BOLT10 - BI-DIRECTIONAL OVERRUNNING
CLUTCH
Fig. 15 Output Flange Seal Installation
1 - DRIVER HANDLE C4171
2 - INSTALLER 8493
Fig. 16 Shim (Select)
1 - SHIM (SELECT)
2 - DIFFERENTIAL PINION
3 - 30 REAR DRIVELINE MODULERS
REAR DRIVELINE MODULE (Continued)
Page 130 of 2585
(4) Install viscous coupler to differential pinion
shaft (Fig. 17).
(5) Install overrunning clutch assembly to viscous
coupler (Fig. 18).
(6) Install washer to overrunning clutch (Fig. 14).
(7) Install o-ring to overrunning clutch (Fig. 14).(8) Align overrunning clutch ground tab to 12
o'clock position (Fig. 19).
(9) Install overrunning clutch housing into posi-
tion, making sure ground tab engages with notch in
housing (Fig. 20).
Fig. 17 Viscous Coupler
1 - VISCOUS COUPLER
2 - DIFFERENTIAL PINION
Fig. 18 Overrunning Clutch
1 - OVERRUNNING CLUTCH
2 - VISCOUS COUPLER
Fig. 19 Grounding Tab at 12 O'clock
1 - OVERRUNNING CLUTCH
2 - GROUND TAB
Fig. 20 Overrunning Clutch Housing
1 - OVERRUNNING CLUTCH HOUSING
2 - NOTCH
RSREAR DRIVELINE MODULE3-31
REAR DRIVELINE MODULE (Continued)
Page 131 of 2585
(10) Install and torque overrunning clutch hous-
ing-to-differential assembly bolts (Fig. 21) to 60 N´m
(44 ft. lbs.).
(11) Install input flange seal using tool 8802 (Fig.
22).(12) Install flange/shield assembly (Fig. 23).
(13) Install input flange washer and nut. Using
tool 6958 (Fig. 24), torque nut to 135 N´m (100 ft.
lbs.).
Fig. 21 Overrunning Clutch Housing Bolts
1 - OVERRUNNING CLUTCH HOUSING
2 - BOLT (FOUR)
Fig. 22 Input Flange Seal Installation
1 - TOOL 8802
2 - HAMMER
Fig. 23 Input Flange/Shield
1 - INPUT FLANGE/SHIELD
Fig. 24 Input Flange Nut
1 - INPUT FLANGE
2 - TOOL 6958
3 - 32 REAR DRIVELINE MODULERS
REAR DRIVELINE MODULE (Continued)
Page 132 of 2585

(14) Install torque arm assembly into position.
Install and torque torque arm-to-differential assem-
bly bolts (Fig. 25) to 60 N´m (44 ft. lbs.).
INSTALLATION
(1) Install rear driveline module assembly to
transmission jack and secure.
(2) Raise rear driveline module into position and
install and torque mounting bolts (Fig. 26) to 54 N´m
(40 ft. lbs.).(3) Remove transmission jack.
(4) Install and torque torque arm mount-to-body
bolts to 54 N´m (40 ft. lbs.).
(5) Install halfshafts to differential output flanges
and torque bolts (Fig. 27) to 61 N´m (45 ft. lbs.).
(6) Install propeller shaft. (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/PROPELLER SHAFT -
INSTALLATION)
(7) Lower vehicle.
Fig. 25 Torque Arm Fasteners
1 - TORQUE ARM ASSEMBLY
2 - BOLT (SIX)
Fig. 26 Rear Drive Line Module Assembly Rear
Mounting Bolts
1 - DRIVELINE MODULE RETAINING BOLT (2)
2 - RUBBER ISOLATOR
3 - WASHER
Fig. 27 Half Shaft Mounting Bolts
1 - SHAFT
2 - FLANGE
RSREAR DRIVELINE MODULE3-33
REAR DRIVELINE MODULE (Continued)
Page 133 of 2585

SPECIFICATIONS - REAR DRIVELINE MODULE
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Bolt, Driveline Module-to-Body 54 40 Ð
Bolt, Halfshaft-to-Ouput Flange 61 45 Ð
Bolt, Overrunning Clutch Housing-to-Differential 60 44 Ð
Bolt, Torque Arm-to-Differential Assembly 60 44 Ð
Bolt, Torque Arm Mount-to-Body 54 40 Ð
Nut, Input Flange 135 100 Ð
Plug, Differential Drain/Fill 35 26 Ð
Plug, Overrunning Clutch Housing Drain/Fill 30 22 Ð
Vent, Differential/Overrunning Clutch Housing 12 Ð 110
SPECIAL TOOLSBI-DIRECTIONAL
OVERRUNNING CLUTCH
DESCRIPTION
The bi-directional overrunning clutch (BOC) (Fig.
28) works as a mechanical disconnect between the
front and rear axles, preventing torque from being
transferred from the rear axle to the front. The BOC
is a simply an overrunning clutch which works in
both clockwise and counter-clockwise rotations. This
means that when the output (the rear axle) is rotat-
ing faster in one direction than the input (front axle),
there is no torque transmission. But when the input
speed is equal to the output speed, the unit becomes
locked. The BOC provides significant benefits regard-
ing braking stability, handling, and driveline durabil-
ity. Disconnecting the front and the rear driveline
during braking helps to maintain the braking stabil-
ity of an AWD vehicle. In an ABS/braking event, the
locking of the rear wheels must be avoided for stabil-
ity reasons. Therefore brake systems are designed to
lock the front wheels first. Any torque transfer from
the rear axle to the front axle disturbs the ABS/brak-
ing system and causes potential instabilities on a
slippery surface. The BOC de-couples the rear driv-
eline as soon the rear wheels begin to spin faster
than the front wheels (front wheels locked) in order
to provide increased braking stability. Furthermore
the BOC also reduces the likelihood of throttle off
over-steer during cornering. In a throttle off maneu-
ver, the BOC once again de-couples the rear driveline
forcing all the engine brake torque to the front
wheels. This eliminates the chance of lateral slip on
the rear axle and increases it on the front. The vehi-
cle will therefore tend to understeer, a situation
which is considered easier to manage in most circum-
stances. During this maneuver, and during the ABS
braking event, the BOC does not transmit torque
Tool 6958
Tool 8493
Tool 8802
3 - 34 REAR DRIVELINE MODULERS
REAR DRIVELINE MODULE (Continued)
Page 134 of 2585
through to the rear wheels. The rear driveline mod-
ule, with the BOC, will perform the same as a front
wheel drive vehicle during these events. The gear
ratio offset between the front and rear differentials
force the BOC into the overrunning mode most of thetime. This allows BOC to significantly reduce the
rolling resistance of the vehicle, which improves fuel
consumption, allows the downsizing of the driveline
components, and prevents the PTU and propshaft
joints from overheating.
Fig. 28 Bi-directional Overrunning Clutch and Viscous Coupler
1 - POWERFLOW - BOC OVERUNNING 6 - VISCOUS COUPLER
2 - POWERFLOW - BOC LOCKED 7 - BOC ROLLER CAGE
3 - BOC GROUND TAB 8 - BOC INPUT SHAFT
4 - FRICTION BRAKE SHOES 9 - INPUT FLANGE
5 - BOC ROLLERS
RSREAR DRIVELINE MODULE3-35
BI-DIRECTIONAL OVERRUNNING CLUTCH (Continued)