
To keep the rollers in the overrunning position and
avoid undesired9high speed lockup9, a high speed
latch (Fig. 33) positions the cage before the ground
shoes lift off. A further explanation of the high speed
effects follows as well. Utilizing only the friction
shoes approach means that at high speed the
required ground shoe drag torque would cause exces-
sive brake shoe wear or the roller will begin to
migrate to the opposite side of the flat due to the
drag force of the outer race. This would result in sys-
tem lock-up. (Fig. 34) shows the BOC as it crosses
the speed where the brake shoe force is overcome by
the roller drag on the outer race. Notice that the
roller is locking up on the opposite side of the flat
and the cage supplies no force on the rollers.
This lock-up is not desired, and requires the use of
another mechanism to prevent the lock-up. The
device that prevents undesired high-speed lock-up is
called a9high speed latch9.
Similar to the friction shoes, the two-piece high-
speed latch will separate from each other at high
rotational speeds due to centrifugal effects. (Fig. 35)
shows the high speed latch engaged. The gap9x9
increases with speed, eventually locking into one of
the slots in the BOC shaft. When the high-speed
latch is activated (propeller shaft speed reaches X
amount), the cage is partially fixed, and cannot lock
on the wrong side of the flat as shown (Fig. 34). Thehigh speed latch is a one way device and does not
prevent high-speed lockup in the reverse direction. At
high speeds, the BOC provides the same function as
low speeds, transferring torque to the viscous coupler
only when front wheel slip overcomes the axle ratio
offset.
At high speed, the rollers are forced outward to the
outer race because of centrifugal force. At high
speeds, the friction shoes can no longer prevent lock-
up. When the teeth on the high-speed latch engage
into the input shaft, it keeps the rollers centered
above the flats because the tabs on the latch are
locked into the cage. (Fig. 36) shows the roller config-
uration with the High-Speed Latch engaged.
On the BOC shaft, the high speed latch teeth lock
up in the grooved areas, shown in (Fig. 37), when the
turning speed reaches the critical value. (Fig. 37)
also shows the outer race/viscous coupler. Notice the
surface (outer race) the rollers mate against when
transferring torque.
Fig. 32 Location of the Grounding Element
1 - DIFFERENTIAL HOUSING
2 - GROUND TAB
3 - GARTER SPRING
Fig. 33 BOC High Speed Latch (Not Engaged)
1 - TOOTH (TWO PLACES)
2 - GARTER SPRING
3 - TABS AT BOTH ENDS FIT INTO SLOTS IN CAGE
4 - TWO PART DESIGN
RSREAR DRIVELINE MODULE3-41
BI-DIRECTIONAL OVERRUNNING CLUTCH (Continued)

DIFFERENTIAL ASSEMBLY
DESCRIPTION
The differential gear system divides the torque
between the axle shafts. It allows the axle shafts to
rotate at different speeds when turning corners.
Each differential side gear is splined to an axle
shaft. The pinion gears are mounted on a pinion
mate shaft and are free to rotate on the shaft. The
pinion gear is fitted in a bore in the differential case
and is positioned at a right angle to the axle shafts.
OPERATION
In operation, power flow occurs as follows:
²The pinion gear rotates the ring gear
²The ring gear (bolted to the differential case)
rotates the case
²The differential pinion gears (mounted on the
pinion mate shaft in the case) rotate the side gears
²The side gears (splined to the axle shafts) rotate
the 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.
38).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.
39). 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.
Fig. 37 BOC Input Shaft
1 - GROOVED AREA (2 LOCATIONS)
2 - ROLLER MATING SURFACE
Fig. 38 Differential OperationÐStraight 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. 39 Differential OperationÐOn Turns
1 - PINION GEARS ROTATE ON PINION SHAFT
RSREAR DRIVELINE MODULE3-43
BI-DIRECTIONAL OVERRUNNING CLUTCH (Continued)

FLUID - DIFFERENTIAL
ASSEMBLY
STANDARD PROCEDURE - DIFFERENTIAL
ASSEMBLY FLUID CHANGE
The drain plug (Fig. 40) for the differential assem-
bly is located in the bottom of the differential assem-
bly case, toward the rear of the unit.
The fill plug (Fig. 41) for the differential assembly
is located on the rear of the assembly case.The correct fill level is to the bottom of the fill plug
hole. Be sure the vehicle is on a level surface, or is
hoisted in a level manner, in order to obtain the cor-
rect fill level.
(1) Raise the vehicle on a hoist.
(2) Position a drain pan under the differential
drain plug (Fig. 40).
(3) Remove the drain plug and allow the fluid to
drain into the pan.
(4) Install the drain plug and torque to 35 N´m (26
ft. lbs.).
(5) Re-position the drain pan under the differential
fill plug.
(6) Remove the differential fill plug (Fig. 41).
(7) Using a suction gun (Fig. 42) or equivalent, fill
the differential assembly with 0.7 L (1.48 pts.) of
MopartGear and Axle Lubricant (80W-90).
(8) Install the fill plug and torque to 35 N´m (26 ft.
lbs.).
FLUID
STANDARD PROCEDURE - OVERRUNNING
CLUTCH HOUSING FLUID CHANGE
(1) Raise vehicle on hoist.
(2) Position a drain pan under overrunning clutch
housing drain plug.
Fig. 40 Differential Drain Plug
1 - DIFFERENTIAL DRAIN PLUG
Fig. 41 Differential Fill Plug
1 - DIFFERENTIAL FILL PLUG
Fig. 42 Filling Differential
1 - DIFFERENTIAL ASSEMBLY
2 - SUCTION GUN
3 - 44 REAR DRIVELINE MODULERS

When a high speed difference (shear) occurs
because of loss of traction (one axle spinning faster
than the other), the silicone fluid expands as it heats
from this shearing. When the silicone expands to fill
the viscous coupler completely, this pressure differ-
ence is high enough to squeeze each pair of plates
together. The resulting hump torque is up to 8 times
higher than the shear torque. When the viscous cou-
pler is in the hump mode, it does not lock the axles
(undifferentiated 4-Wheel Drive). It controls the
amount of slippage while delivering maximum power
to the axle having greatest traction. Once the speed
difference equalizes the fluid and plates cool down
and the viscous coupler goes back to the shear mode.
TORQUE ARM
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove rear driveline module assembly. (Refer
to 3 - DIFFERENTIAL & DRIVELINE/REAR DRIV-
ELINE MODULE - REMOVAL)
(3) Remove six torque arm-to-differential assembly
bolts (Fig. 47). Remove torque arm.
INSTALLATION
(1) Install six torque arm-to-differential assembly
bolts (Fig. 47) and torque to 60 N´m (44 ft. lbs.).
(2) Install rear driveline module assembly. (Refer
to 3 - DIFFERENTIAL & DRIVELINE/REAR DRIV-
ELINE MODULE - INSTALLATION)
(3) Lower vehicle.
INPUT FLANGE SEAL
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove propeller shaft. (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/PROPELLER SHAFT -
REMOVAL)
(3) Using tool 6958, remove input flange nut and
washer (Fig. 48).
(4) Remove input flange (Fig. 49).
(5) Using suitable screwdriver, remove input
flange seal from overrunning clutch housing (Fig.
50).
INSTALLATION
(1) Using tool 8802, install input flange seal to
overrunning clutch case (Fig. 51).
(2) Install input flange (Fig. 52).
(3) Install flange nut and washer. Using tool 6958,
torque flange nut to 135 N´m (100 ft. lbs.) (Fig. 53).
(4) Install propeller shaft. (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/PROPELLER SHAFT -
INSTALLATION)
(5) Lower vehicle.
Fig. 47 Torque Arm Fasteners
1 - TORQUE ARM ASSEMBLY
2 - BOLT (SIX)
Fig. 48 Input Flange Nut
1 - INPUT FLANGE
2 - TOOL 6958
RSREAR DRIVELINE MODULE3-47
VISCOUS COUPLER (Continued)

OUTPUT FLANGE SEAL
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove rear halfshaft inner joint at differen-
tial output flange (Fig. 54).
(3) Using two screwdrivers and wood blocks to pro-
tect differential housing casting, pry output flange
out of differential (Fig. 55).
(4) Use suitable screwdriver to remove output
flange seal (Fig. 56).
Fig. 53 Input Flange Nut
1 - INPUT FLANGE
2 - TOOL 6958
Fig. 54 Inner Half Shaft Bolts
1 - SHAFT
2 - FLANGE
Fig. 55 Output Flange Removal
1 - WOOD BLOCK
2 - PRYBAR
3 - OUTPUT SHAFT
4 - PRYBAR
5 - WOOD BLOCK
6 - DIFFERENTIAL CASE
Fig. 56 Output Flange Seal Removal
1 - OUTPUT FLANGE SEAL
2 - SCREWDRIVER
RSREAR DRIVELINE MODULE3-49
INPUT FLANGE SEAL (Continued)

INSTALLATION
(1) Install output flange seal to differential hous-
ing using tool C4171A and 8493 (Fig. 57).(2) Install ouput flange to differential assembly.
Verify that it is seated all the way into position by
attempting to pull out by hand.
(3) Install rear halfshaft inner joint to output
flange.
(4) Install and torque bolts to 61 N´m (45 ft. lbs.)
(Fig. 58).
(5) Check differential assembly fluid level and
adjust as required. (Refer to 3 - DIFFERENTIAL &
DRIVELINE/REAR DRIVELINE MODULE/FLUID -
STANDARD PROCEDURE)
Fig. 57 Output Flange Seal Installation
1 - DRIVER HANDLE C4171
2 - INSTALLER 8493Fig. 58 Inner Half Shaft Bolts
1 - SHAFT
2 - FLANGE
3 - 50 REAR DRIVELINE MODULERS
OUTPUT FLANGE SEAL (Continued)

INSTALLATION - WHEEL SPEED SENSOR
(REAR-FWD)
CAUTION: Proper installation of wheel speed sen-
sor cable is critical to continued system operation.
Be sure that cable is installed in routing retainers/
clips. Failure to install cable in retainers may result
in contact with moving parts or over extension of
cable, resulting in an open circuit.
NOTE: Make sure wheel speed sensor stays clean
and dry as it is installed into the hub and bearing
cap.
(1) If metal sensor retaining clip is not in the neu-
tral installed position on hub and bearing cap, install
from the bottom, if necessary, and push clip upward
until it snaps into position.
(2) Install wheel speed sensor head into rear of
hub and bearing aligning index tab with the notch in
the top of the mounting hole. Push the sensor in
until it snaps into place on the metal retaining clip.
(3) Install secondary (yellow) retaining clip over
wheel speed sensor head and engage the tabs on each
side.
(4) Route sensor cable under leaf spring along rear
of axle. Install speed sensor cable into routing clips
on rear brake flex hose (Fig. 4).
(5) Install cable into metal routing clip and attach
it to the rear axle with mounting bolt (Fig. 4).
Tighten mounting bolt to 16 N´m (140 in. lbs.).
(6) Connect wheel speed sensor cable to vehicle
wiring harness (Fig. 3).Be sure speed sensor
cable connector is fully seated and locked into
vehicle wiring harness connector.
(7) Install speed sensor cable grommet into hole in
floor pan making sure grommet is fully seated into
hole.
(8) Lower vehicle.
(9) Road test vehicle to ensure proper operation of
the base and ABS braking systems.
TONE WHEEL
INSPECTION - TONE WHEEL
NOTE: Rear tone wheels for front-wheel-drive vehi-
cles are sealed within the hub and bearing assem-
bly and cannot be inspected or replaced.
Replacement of the hub and bearing is necessary.Tone wheels can cause erratic wheel speed sensor
signals. Inspect tone wheels for the following possible
causes.
²missing, chipped, or broken teeth
²contact with the wheel speed sensor
²wheel speed sensor to tone wheel alignment
²wheel speed sensor to tone wheel clearance
²excessive tone wheel runout
²tone wheel loose on its mounting surface
If a front tone wheel is found to need replacement,
the drive shaft must be replaced. No attempt should
be made to replace just the tone wheel. (Refer to 3 -
DIFFERENTIAL & DRIVELINE/HALF SHAFT -
REMOVAL)
If a rear tone wheel is found to need replacement
on an all-wheel-drive model, the drive shaft must be
replaced. No attempt should be made to replace just
the tone wheel. (Refer to 3 - DIFFERENTIAL &
DRIVELINE/HALF SHAFT - REMOVAL)
If wheel speed sensor to tone wheel contact is evi-
dent, determine the cause and correct it before
replacing the wheel speed sensor or tone wheel.
Check the gap between the speed sensor head and
the tone wheel to ensure it is within specifications.
(Refer to 5 - BRAKES - ABS/ELECTRICAL - SPEC-
IFICATIONS)
Excessive wheel speed sensor runout can cause
erratic wheel speed sensor signals. Refer to SPECI-
FICATIONS in this section of the service manual for
the maximum allowed tone wheel runout (Refer to 5 -
BRAKES - ABS/ELECTRICAL - SPECIFICATIONS).
If tone wheel runout is excessive, determine if it is
caused by a defect in the driveshaft assembly or hub
and bearing. Replace as necessary.
Tone wheels are pressed onto their mounting sur-
faces and should not rotate independently from the
mounting surface. Replacement of the front drive-
shaft, rear driveshaft (AWD only) or rear hub and
bearing is necessary.
TRACTION CONTROL SWITCH
DIAGNOSIS AND TESTING - TRACTION
CONTROL SWITCH
(1) Remove lower column shroud.
(2) Disconnect traction control switch harness from
column harness below column.
(3) Using an ohmmeter, check for continuity read-
ing between pins. Refer to test table and (Fig. 6).
5 - 74 BRAKES - ABSRS
REAR WHEEL SPEED SENSOR - FWD (Continued)

(24) Disconnect egr solenoid vacuum line at brake
booster check valve.
(25) Disconnect fuel injector, cam sensor, boost
pressure/intake air temp sensor, fuel rail high pres-
sure, and egr solenoid connectors (Fig. 9).
(26) Disconnect generator electrical connectors.
(27) Disconnect coolant temp sensor and glow plug
electrical connectors.
(28) Disconnect injection pump and A/C compres-
sor electrical connectors.
(29) Disconnect starter electrical connectors.
(30) Disconnect ground wires at engine block.
(31) Raise vehicle on hoist.
(32) Disconnect oil temp sensor, oil pressure sen-
sor, engine speed sensor, and vehicle speed sensor
electrical connector (Fig. 10).
(33) Remove front wheels.
(34) Remove the suspension cradle assembly (Refer
to 13 - FRAME & BUMPERS/FRAME/ENGINE
CRADLE CROSSMEMBER - REMOVAL).
(35) Remove both axle shaft assemblies (Refer to 3
- DIFFERENTIAL & DRIVELINE/HALF SHAFT -
REMOVAL).(36) Disconnect the clutch slave cylinder quick dis-
connect line (RHD only)(Refer to 6 - CLUTCH/SLAVE
CYLINDER - REMOVAL).
(37) Disconnect reverse lamp connector.
(38) Disconnect shifter cables at the tranmission
(Refer to 21 - TRANSMISSION/TRANSAXLE/MAN-
UAL/GEAR SHIFT CABLE - REMOVAL).
(39) Disconnect exhaust pipe from the turbo-
charger downpipe and reposition to right side of vehi-
cle.
(40) Disconnect cabin heater coolant line (Refer to
24 - HEATING & AIR CONDITIONING/CABIN
HEATER/HEATER UNIT - REMOVAL).
(41) Remove front engine mount bracket retaining
bolts from lower radiator support
(42) Lower vehicle. Evacuate the A/C system
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING/REFRIGERANT - STANDARD PROCE-
DURE).
(43) Disconnect the A/C lines at the A/C compres-
sor.
(44) Disconnect the fuel supply and return lines.
(45) Position engine cradle under engine and lower
vehicle over cradle.
(46) Remove right engine mount bolts.
Fig. 7 CHARGE AIR COOLER HOSES
1 - COOLING MODULE
2 - BYPASS HOSE
3 - UPPER RADIATOR HOSE
4 - CHARGE AIR COOLER OULET HOSE
5 - CHARGE AIR COOLER INLET HOSE
6 - LOWER RADIATOR HOSE
7 - CHARGE AIR COOLER
Fig. 8 UPPER AND LOWER RADIATOR HOSES
1 - COOLANT BYPASS HOSE
2 - RADIATOR ASSEMBLY
3 - UPPER RADIATOR HOSE
4 - COOLING FAN
5 - LOWER RADIATOR HOSE
6 - CHARGE AIR COOLER
7 - RADIATOR BRACKET
RGENGINE 2.5L TURBO DIESEL9a-5
ENGINE 2.5L TURBO DIESEL (Continued)