2002 JEEP LIBERTY rear differential

(7) Hold pinion yoke with Holder 6719A and
remove pinion yoke nut and washer.
(8) Remove pinion yoke from pinion shaft with
Remover C-452 (Fig. 48).
(9) Remove pinion from the housing (Fig. 49).
Fig. 46 Differential Bearing Installer
1 - HANDLE
2 - DIFFERENTIAL
3 - BEARING
4 - INSTALLER
Fig. 47 Ring Gear
1 - CASE
2 - RING GEAR
3 - RAWHIDE HAMMER
Fig. 48 Pinion Yoke
1 - PINION YOKE
2 - REMOVER
Fig. 49 Pinion Gear
1 - RAWHIDE HAMMER
KJREAR AXLE - 8 1/4 3 - 111
PINION GEAR/RING GEAR/TONE RING (Continued)

(4) Install pinion front bearing and oil slinger, if
equipped.(5) Apply a light coating of gear lubricant on the
lip of pinion seal and install seal with Installer
C-4076-B and Handle C-4735 (Fig. 56).
(6) Place proper thickness depth shim on the pin-
ion.
(7) Install rear bearing and slinger if equipped, on
the pinion shaft (Fig. 57) with Installer 6448 and a
press.
(8) Install anewcollapsible preload spacer on pin-
ion shaft and install pinion in housing (Fig. 58).
(9) Install pinion in housing.
(10) Install yoke with Installer C-3718 and Yoke
Holder 6719A.
Fig. 53 Rear Pinion Bearing Puller
1 - PULLER
2 - VISE
3 - ADAPTERS
4 - PINION GEAR SHAFT
Fig. 54 Rear Pinion Bearing Cup
1 - INSTALLER
2 - HANDLE
Fig. 55 Front Bearing Cup
1 - INSTALLER
2 - HANDLE
Fig. 56 Pinion Seal
1 - HANDLE
2 - DIFFERENTIAL HOUSING
3 - INSTALLER
KJREAR AXLE - 8 1/4 3 - 113
PINION GEAR/RING GEAR/TONE RING (Continued)

(15) Invert the differential case.
(16) Install ring gear on the differential case and
start two ring gear bolts. This will provide case-to-
ring gear bolt hole alignment.
(17) Invert the differential case in the vise.
(18) Installnewring gear bolts and alternately
tighten to 102 N´m (75 ft. lbs.) (Fig. 60).
CAUTION: Never reuse the ring gear bolts. The
bolts can fracture causing extensive damage.
(19) Install differential in axle housing and verify
gear mesh refer to Adjustments (Gear Contact Pat-
tern).
(20) Install differential cover fill with gear lubri-
cant.
(21) Install the propeller shaft with reference
marks aligned.
(22) Install wheel and tire assemblies and lower
the vehicle.
Fig. 60 Ring Gear
1 - TORQUE WRENCH
2 - BOLTS
3 - RING GEAR
4 - DIFFERENTIAL CASE
KJREAR AXLE - 8 1/4 3 - 115
PINION GEAR/RING GEAR/TONE RING (Continued)

DIAGNOSIS AND TESTING - MASTER
CYLINDER/POWER BOOSTER...........21
REMOVAL.............................22
INSTALLATION.........................23
MASTER CYLINDER
DESCRIPTION.........................24
OPERATION...........................24
DIAGNOSIS AND TESTING - MASTER
CYLINDER/POWER BOOSTER...........24
STANDARD PROCEDURE - MASTER
CYLINDER BLEEDING..................24
REMOVAL.............................25
INSTALLATION.........................25
FLUID RESERVOIR
REMOVAL.............................26
INSTALLATION.........................26
FLUID
DIAGNOSIS AND TESTING - BRAKE FLUID
CONTAMINATION.....................26
STANDARD PROCEDURES - MASTER
CYLINDER FLUID LEVEL................26
SPECIFICATIONS
BRAKE FLUID........................27
DRUM
DIAGNOSIS AND TESTING - BRAKE DRUM . . . 27
STANDARD PROCEDURES - BRAKE DRUM
MACHINING..........................27SUPPORT PLATE
REMOVAL
REMOVAL - 198 RBI AXLE..............27
REMOVAL - 8 1/4 AXLE.................27
INSTALLATION
INSTALLATION - 198 RBI AXLE...........28
INSTALLATION - 8 1/4 AXLE.............28
WHEEL CYLINDERS
REMOVAL.............................28
DISASSEMBLY.........................28
CLEANING............................28
INSPECTION..........................29
ASSEMBLY............................29
INSTALLATION.........................29
PARKING BRAKE
DESCRIPTION.........................29
OPERATION...........................29
ADJUSTMENTS
ADJUSTMENT - LOCK OUT.............30
CABLES
REMOVAL.............................30
INSTALLATION.........................30
LEVER
REMOVAL.............................31
INSTALLATION.........................31
BRAKES - BASE
DESCRIPTION
Power assist front disc and rear drum brakes are
standard equipment. Disc brake components consist
of single piston calipers and ventilated rotors. Rear
drum brakes are dual shoe units with cast brake
drums.
The parking brake mechanism is lever and cable
operated. The cables are attached to levers on the
rear drum brake secondary shoes. The parking
brakes are operated by a hand lever.
A dual diaphragm vacuum power brake booster is
used for all applications. All models have an alumi-
num master cylinder with plastic reservoir.
All models are equipped with a combination valve.
The valve contains a pressure differential valve and
switch and a fixed rate rear proportioning valve.
Factory brake lining on all models consists of an
organic base material combined with metallic parti-
cles. The original equipment linings do not contain
asbestos.
WARNING
WARNING: DUST AND DIRT ACCUMULATING ON
BRAKE PARTS DURING NORMAL USE MAY CON-
TAIN ASBESTOS FIBERS FROM AFTERMARKET
LININGS. BREATHING EXCESSIVE CONCENTRA-
TIONS OF ASBESTOS FIBERS CAN CAUSE SERI-
OUS BODILY HARM. EXERCISE CARE WHEN
SERVICING BRAKE PARTS. DO NOT CLEAN
BRAKE PARTS WITH COMPRESSED AIR OR BY
DRY BRUSHING. USE A VACUUM CLEANER SPE-
CIFICALLY DESIGNED FOR THE REMOVAL OF
ASBESTOS FIBERS FROM BRAKE COMPONENTS.
IF A SUITABLE VACUUM CLEANER IS NOT AVAIL-
ABLE, CLEANING SHOULD BE DONE WITH A
WATER DAMPENED CLOTH. DO NOT SAND, OR
GRIND BRAKE LINING UNLESS EQUIPMENT USED
IS DESIGNED TO CONTAIN THE DUST RESIDUE.
DISPOSE OF ALL RESIDUE CONTAINING ASBES-
TOS FIBERS IN SEALED BAGS OR CONTAINERS
TO MINIMIZE EXPOSURE TO YOURSELF AND OTH-
ERS. FOLLOW PRACTICES PRESCRIBED BY THE
OCCUPATIONAL SAFETY AND HEALTH ADMINIS-
TRATION AND THE ENVIRONMENTAL PROTECTION
AGENCY FOR THE HANDLING, PROCESSING, AND
DISPOSITION OF DUST OR DEBRIS THAT MAY
CONTAIN ASBESTOS FIBERS.
5 - 2 BRAKES - BASEKJ

POWER BRAKE BOOSTER
DESCRIPTION
The booster assembly consists of a housing divided
into separate chambers by two internal diaphragms.
The outer edge of each diaphragm is attached to the
booster housing. The diaphragms are connected to
the booster primary push rod.
Two push rods are used in the booster. The pri-
mary push rod connects the booster to the brake
pedal. The secondary push rod connects the booster
to the master cylinder to stroke the cylinder pistons.
OPERATION
The atmospheric inlet valve is opened and closed
by the primary push rod. Booster vacuum supply is
through a hose attached to an intake manifold fitting
at one end and to the booster check valve at the
other. The vacuum check valve in the booster housing
is a one-way device that prevents vacuum leak back.
Power assist is generated by utilizing the pressure
differential between normal atmospheric pressure
and a vacuum. The vacuum needed for booster oper-
ation is taken directly from the engine intake mani-
fold. The entry point for atmospheric pressure is
through a filter and inlet valve at the rear of the
housing (Fig. 33).
The chamber areas forward of the booster dia-
phragms are exposed to vacuum from the intake
manifold. The chamber areas to the rear of the dia-
phragms, are exposed to normal atmospheric pres-
sure of 101.3 kilopascals (14.7 pounds/square in.).Brake pedal application causes the primary push
rod to open the atmospheric inlet valve. This exposes
the area behind the diaphragms to atmospheric pres-
sure. The resulting pressure differential provides the
extra apply force for power assist.
The booster check valve, check valve grommet and
booster seals are serviceable.
DIAGNOSIS AND TESTING - MASTER
CYLINDER/POWER BOOSTER
(1) Start engine and check booster vacuum hose
connections. A hissing noise indicates vacuum leak.
Correct any vacuum leak before proceeding.
(2) Stop engine and shift transmission into Neu-
tral.
(3) Pump brake pedal until all vacuum reserve in
booster is depleted.
(4) Press and hold brake pedal under light foot
pressure. The pedal should hold firm, if the pedal
falls away master cylinder is faulty (internal leak-
age).
(5) Start engine and note pedal action. It should
fall away slightly under light foot pressure then hold
firm. If no pedal action is discernible, power booster,
vacuum supply, or vacuum check valve is faulty. Pro-
ceed to the POWER BOOSTER VACUUM TEST.
(6) If the POWER BOOSTER VACUUM TEST
passes, rebuild booster vacuum reserve as follows:
Release brake pedal. Increase engine speed to 1500
rpm, close the throttle and immediately turn off igni-
tion to stop engine.
(7) Wait a minimum of 90 seconds and try brake
action again. Booster should provide two or more vac-
uum assisted pedal applications. If vacuum assist is
not provided, booster is faulty.
POWER BOOSTER VACUUM TEST
(1) Connect vacuum gauge to booster check valve
with short length of hose and T-fitting (Fig. 34).
(2) Start and run engine at curb idle speed for one
minute.
(3) Observe the vacuum supply. If vacuum supply
is not adequate, repair vacuum supply.
(4) Clamp hose shut between vacuum source and
check valve.
(5) Stop engine and observe vacuum gauge.
(6) If vacuum drops more than one inch Hg (33
millibars) within 15 seconds, booster diaphragm or
check valve is faulty.
POWER BOOSTER CHECK VALVE TEST
(1) Disconnect vacuum hose from check valve.
(2) Remove check valve and valve seal from
booster.
(3) Use a hand operated vacuum pump for test.
Fig. 32 BOOSTER PUSH ROD
1 - MASTER CYLINDER ASSEMBLY
2 - BRAKE BOOSTER
3 - CLIP
4 - BRAKE PEDAL
5 - BOOSTER ROD
KJBRAKES - BASE 5 - 21
PEDAL (Continued)

REAR WHEEL SPEED SENSOR
REMOVAL
(1) Raise vehicle on hoist.
(2) Disconnect the sensor wire harness.
(3) Remove mounting stud from the sensor (Fig. 2).
(4) Remove sensor.
INSTALLATION
(1) Connect harness to sensor.Be sure seal is
securely in place between sensor and wiring
connector.
(2) Install O-ring on sensor (if removed).
(3) Insert sensor in differential housing.
(4) Install the sensor mounting stud and tighten to
9 N´m (80 in. lbs.).
(5) Install the sensor electical connector.
(6) Lower vehicle.
HCU (HYDRAULIC CONTROL
UNIT)
DESCRIPTION
The HCU consists of a valve body, pump motor,
and wire harness.
OPERATION
Accumulators in the valve body store extra fluid
released to the system for ABS mode operation. The
pump provides the fluid volume needed and is oper-
ated by a DC type motor. The motor is controlled by
the CAB.The valves modulate brake pressure during
antilock braking and are controlled by the CAB.
The HCU provides three channel pressure control
to the front and rear brakes. One channel controls
the rear wheel brakes in tandem. The two remaining
channels control the front wheel brakes individually.
During antilock braking, the solenoid valves are
opened and closed as needed. The valves are not
static. They are cycled rapidly and continuously to
modulate pressure and control wheel slip and decel-
eration.
During normal braking, the HCU solenoid valves
and pump are not activated. The master cylinder and
power booster operate the same as a vehicle without
an ABS brake system.
During antilock braking, solenoid valve pressure
modulation occurs in three stages, pressure increase,
pressure hold, and pressure decrease. The valves are
all contained in the valve body portion of the HCU.
PRESSURE DECREASE
The outlet valve is opened and the inlet valve is
closed during the pressure decrease cycle.
A pressure decrease cycle is initiated when speed
sensor signals indicate high wheel slip at one or
more wheels. At this point, the CAB closes the inlet
then opens the outlet valve, which also opens the
return circuit to the accumulators. Fluid pressure is
allowed to bleed off (decrease) as needed to prevent
wheel lock.
Once the period of high wheel slip has ended, the
CAB closes the outlet valve and begins a pressure
increase or hold cycle as needed.
PRESSURE HOLD
Both solenoid valves are closed in the pressure
hold cycle. Fluid apply pressure in the control chan-
nel is maintained at a constant rate. The CAB main-
tains the hold cycle until sensor inputs indicate a
pressure change is necessary.
PRESSURE INCREASE
The inlet valve is open and the outlet valve is
closed during the pressure increase cycle. The pres-
sure increase cycle is used to counteract unequal
wheel speeds. This cycle controls re-application of
fluid apply pressure due to changing road surfaces or
wheel speed.
Fig. 2 REAR WHEEL SPEED SENSOR
1 - DIFFERENTIAL HOUSING
2 - MOUNTING BOLT
3 - WHEEL SPEED SENSOR
KJBRAKES - ABS 5 - 35

SPECIFICATIONS - TORQUE
DESCRIPTION N´m Ft. Lbs. In. Lbs.
ENGINE CRADLE CROSSMEMBER INNER RAIL BOLTS 47 35 Ð
ENGINE CRADLE CROSSMEMBER MOUNTING BOLTS 122 90 Ð
ENGINE MOUNT THROUGH BOLTS/NUTS 88 65 Ð
FRONT SKID PLATE BOLTS 61 45 Ð
FRONT TOW HOOK NUTS/BOLT 61 45 Ð
FUEL TANK SKID PLATE 88 65 Ð
REAR CROSSMEMBER BOLTS 47 35 Ð
REAR TOW HOOK BOLTS 88 65 Ð
TRAILER HITCH BOLTS 88 65 Ð
TRANSFER CASE SKID PLATE BOLTS 34 25 Ð
TRANSMISSION MOUNT THROUGH BOLT/NUT 88 65 Ð
FRONT SKID PLATE
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the skid plate bolts and remove the
skid plate. (Fig. 7)
INSTALLATION
(1) Install the skid plate.
(2) Install the bolts and tighten to 61 N´m (45 ft.
lbs.).
ENGINE CRADLE
CROSSMEMBER
REMOVAL
(1) Install a suitable engine support tool.
(2) Raise and support the vehicle.
(3) Remove the lower control arms. (Refer to 2 -
SUSPENSION/FRONT/LOWER CONTROL ARM -
REMOVAL)
(4) Remove the sway bar. (Refer to 2 - SUSPEN-
SION/FRONT/STABILIZER BAR - REMOVAL)
(5) Remove the front axle, if equipped. (Refer to 3 -
DIFFERENTIAL & DRIVELINE/FRONT AXLE -
REMOVAL)
(6) Remove the power steering rack. (Refer to 19 -
STEERING/GEAR - REMOVAL)
(7) Loosen the engine mount through bolts.
(8) Support the engine cradle with a suitable lift-
ing device.
(9) Using a grease pencil or equivalent, mark the
location of the engine support cradle.
(10) Remove the engine cradle bolts and remove
the engine cradle.
INSTALLATION
(1) Raise and support the vehicle.
(2) Using a suitable lifting device raise the engine
cradle into the vehicle while lining up the engine
mount through bolts.
Fig. 7 SKID PLATE
1 - SKID PLATE
2 - BOLTS (4)
13 - 6 FRAMES & BUMPERSKJ
FRAME (Continued)

(3) Align the engine cradle to the marks made dur-
ing removal and install the mounting and inner rail
bolts.
(4) Tighten the mounting bolts to 122 N´m (90 ft.
lbs.).
(5) Tighten the inner rail bolts to 47 N´m (35 ft.
lbs.).
(6) Tighten the engine mount through bolts to 88
N´m (65 ft. lbs.).
(7) Install the power steering rack. (Refer to 19 -
STEERING/GEAR - INSTALLATION)
(8) Install the front axle, if equipped. (Refer to 3 -
DIFFERENTIAL & DRIVELINE/FRONT AXLE -
INSTALLATION)
(9) Install the stabilizer bar. (Refer to 2 - SUS-
PENSION/FRONT/STABILIZER BAR - INSTALLA-
TION)
(10) Install the lower control arms. (Refer to 2 -
SUSPENSION/FRONT/LOWER CONTROL ARM -
INSTALLATION)
(11) Lower the vehicle and remove the engine sup-
port tool.
TRANSFER CASE SKID PLATE
REMOVAL
(1) Remove the bolts and remove the skid plate.
(Fig. 8)
INSTALLATION
(1) Install the skid plate.
(2) Install the bolts and tighten to 34 N´m (25 ft.
lbs.).
REAR CROSSMEMBER
REMOVAL
(1) Raise and support the vehicle.
(2) Support the transmission with a suitable lifting
device.
(3) Remove the transmission mount through bolt.
(4) Remove the crossmember bolts and remove the
crossmember. (Fig. 9)
INSTALLATION
(1) Install the crossmember and install the bolts.
(2) Tighten the bolts to 47 N´m (35 ft. lbs.)
(3) Install transmission mount through bolt and
tighten to 88 N´m (65 ft. lbs.).
Fig. 8 SKID PLATE
1 - SKID PLATE
2 - BOLTS
Fig. 9 CROSS MEMBER
1 - CROSSMEMBER
2 - BOLTS
KJFRAMES & BUMPERS 13 - 7
ENGINE CRADLE CROSSMEMBER (Continued)