JEEP CHEROKEE 1995 Service Repair Manual

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(5) Use torque wrench on Special Tool 6790 to ro-
tate wheel and read rotating torque (Fig. 2).
(6) If rotating torque is less than 22 Nzm (30 ft.
lbs.) or more than 271 Nzm (200 ft. lbs.) on either
wheel the unit should be service.
DIFFERENTIAL OVERHAUL
The Trac-Lok differential components are illus-
trated in (Fig. 3). Refer to this illustration during re-
pair service.
DISASSEMBLY
Service to the Trac-Lok differential requires the
use of Tool Set C-4487 (J-23781). Refer to Model 35
Axle section in this Group for Differential Removal
and Installation.
(1) Clamp one axle shaft in a vise equipped with
soft jaws (Fig. 4).
Fig. 3 Trac-Lok Differential Components
Fig. 2 Trac-Loc Test
Fig. 4 Axle Shaft As Holding Fixture
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(2) Position the differential case on the axle shaft
(Fig. 5). Place shop towels under the differential to
avoid damage during removal of the ring gear (Fig.
5).
(3) Remove and discard the ring gear bolts. Tap
the ring gear with a rawhide or plastic mallet and re-
move (Fig. 6).
(4) Remove the pinion gear mate shaft lock screw
(Fig. 7).
(5) Remove the pinion gear mate shaft with a drift
and hammer (Fig. 8).
(6) Install and lubricate Step Plate C-4487-1 (Fig.
9).
(7) Assemble Threaded Adapter C-4487-3 into top
side gear. Thread forcing Screw C-4487-2 into
adapter until it becomes centered in adapter plate.
Fig. 7 Mate Shaft Lock Screw
Fig. 8 Mate Shaft Removal
Fig. 9 Step Plate Tool Installation
Fig. 5 Differential Case On Shaft
Fig. 6 Ring Gear Removal
JREAR SUSPENSION AND AXLES 3 - 47

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(8) Position a small screw driver in slot of
Threaded Adapter C-4487-3 (Fig. 10 to prevent
adapter from turning.
(9) Tighten forcing screw tool enough to relieve
clutch pack tension. Remove both pinion thrust
washers (Fig. 11).
(10) Loosen the forcing screw tool until the clutch
pack tension is relieved.
(11) Insert Turning Bar C-4487-4 in case. Rotate
case with tool until pinion gears can be removed (Fig.
12).(12) Remove top side gear and clutch pack. Keep
plates in correct order during removal (Fig. 13).
(13) Remove case from fixture. Remove remaining
clutch pack.
(14) Remove clutch pack retaining clips. Mark each
clutch pack for installation reference.
CLEANING AND INSPECTION
(1) Clean all components in cleaning solvent. Dry
components with compressed air.
Fig. 10 Threaded Adapter Installation
Fig. 11 Remove Pinion Thrust Washer
Fig. 12 Pinion Gear Removal
Fig. 13 Side Gear & Clutch Disc Removal
3 - 48 REAR SUSPENSION AND AXLESJ

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(2) Inspect clutch pack plates for wear, scoring or
damage. Replace both clutch packs if any one compo-
nent in either pack is damaged.
(3) Inspect side and pinion gears. Replace any gear
that is worn, cracked, chipped or damaged.
(4) Inspect differential case and pinion shaft. Re-
place if worn or damaged.
PRESOAK PLATES AND DISC
Plates and dics with fiber coating (no groves or
lines) must be presoaked in Friction Modifier before
assembly. Soak plates and discs for a minimum of 20
minutes. Add remaining Friction Modifier to differen-
tial after assembly.
ASSEMBLY
(1) The clutch discs are replaceable as complete
sets only. If one clutch disc pack is damaged, both
packs must be replaced. Lubricate each component
with gear lubricant before assembly and installation.
(2) Assemble the clutch discs into packs and secure
disc packs with retaining clips (Fig. 14).
(3) Position assembled clutch disc packs on the
side gear hubs.
(4) Position case on axle fixture.
(5) Install clutch pack and side gear in lower bore
(Fig. 15). Be sure clutch pack retaining clips remain
in position and are seated in the case pockets.
(6) Install lubricated Step Plate C-4487-1 on first
clutch pack (Fig. 16).
(7) Install the upper side gear and clutch disc pack
(Fig. 16).
(8) Hold assembly in position. Insert Threaded
Adapter C-4487-3 into top side gear, insert forcing
Screw C-4487-2.(9) Tighten forcing screw tool to compress clutch
discs.
(10) Install pinion gears. Rotate case with Turning
Bar C-4487-4. Make sure holes of pinion mate gears
are aligned with case.
(11) Tighten forcing screw to compress the
Belleville plates. Lubricate and install pinion gear
thrust washers with a small screw driver.
(12) Install pinion gear mate shaft ( align holes in
shaft and case).
(13) Install the pinion mate shaft lock screw finger
tight.
If replacement gears and thrust washers were
installed, it is not necessary to measure the
gear backlash. Correct fit is due to close ma-
chining tolerances during manufacture.
Fig. 14 Clutch Disc Pack
Fig. 15 Clutch Discs & Lower Side Gear Installation
Fig. 16 Upper Side Gear & Clutch Disc Pack
Installation
JREAR SUSPENSION AND AXLES 3 - 49

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(14) Invert the differential case and start two ring
gear bolts. This will provide case-to-ring gear bolt
hole alignment.
(15) Install new ring gear bolts and alternately
tighten to 95-122 Nzm (70-90 ft. lbs.) torque (Fig. 17).
(17) Lubricate all differential components with hy-
poid gear lubricant.
Fig. 17 Ring Gear Bolt Installation
3 - 50 REAR SUSPENSION AND AXLESJ

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AXLE SPECIFICATIONS
MODEL 35 AXLE
Axle Type...............................Semi-Floating Hypoid
Lubricant................SAE Thermally Stable 80W-90
Lubricant Trailer Tow.............Synthetic 75W-140
Lube Capacity..............................1.66 L (3.50 pts.)
Axle Ratio................................3.07, 3.55, 3.73, 4.10
Differential
Bearing Preload ............................0.1 mm (0.004 in.)
Side Gear Clearance ............0-0.15 mm (0-0.006 in.)
Ring Gear
Diameter .......................................19.2 cm (7.562 in.)
Backlash.........................0-0.15 mm (0.005-0.008 in.)
Pinion Std. Depth...................96.8 mm (3.813 in.)
Pinion Bearing Preload
Original Bearing ....................1-2Nzm (10-20 in. lbs.)
New Bearing .......................1.5-4Nzm (15-35 in. lbs.)
8 1/4 AXLE
Axle Type................................Semi-floating, hypoid
Lubricant...............................................SAE 75W-90
Lube Capacity................................2.08 L (4.4 pts.)
Axle Ratios.........................................3.07 3.55 4.10
Differential
Side Gear Clearance ..................0.12 mm (0.005 in.)
Case Flange Runout ..................0.07 mm (0.003 in.)
Bearing Preload ...........................95 Nzm (70 ft. lbs.)
Ring Gear
Diameter .......................................20.95 cm (8.25 in.)
Backlash....................0.12-0.20 mm (0.005-0.008 in.)
Runout .......................................0.127 mm (0.005 in.)
Pinion Bearing
Preload ....................................1-2 Nzm (10-20 in.lbs.)
TORQUE SPECIFICATIONS
XJ REAR SUSPENSION COMPONENTS
DESCRIPTION ................................................TORQUE
Shock Absorber
Upper Bolt ...................................23 Nzm (17 ft. lbs.)
Lower Nut ....................................62 Nzm (46 ft. lbs.)
Stabilizer Bar
Clamp Bolt ...................................54 Nzm (40 ft. lbs.)
Link Upper Bolt ............................12 Nzm (9 ft. lbs.)
Link Lower Nut ..........................74 Nzm (55 ft. lbs.)
Spring
U-Bolt Nut ...................................70 Nzm (52 ft. lbs.)
Front Pivot Bolt ......................148 Nzm (109 ft. lbs.)
Upper Shackle Bolt .................148 Nzm (109 ft. lbs.)
Lower Shackle Bolt ...................108 Nzm (80 ft. lbs.)
YJ REAR SUSPENSION COMPONENTS
DESCRIPTION ................................................TORQUE
Shock Absorber
Upper Nut ....................................61 Nzm (45 ft. lbs.)
Lower Nut ....................................61 Nzm (45 ft. lbs.)
Track Bar
Frame Bracket Nut.................142 Nzm (105 ft. lbs.)
Axle Bracket Nut ....................142 Nzm (105 ft. lbs.)Spring
U-Bolt Nut .................................122 Nzm (90 ft. lbs.)
Rear Shackle Bolts..................136 Nzm (100 ft. lbs.)
Front Pivot Bolt ......................142 Nzm (105 ft. lbs.)
MODEL 35 AXLE
DESCRIPTION ................................................TORQUE
Fill Hole Plug...........................34 Nzm (25 ft. lbs.)
Diff. Cover Bolt........................41 Nzm (30 ft. lbs.)
Bearing Cap Bolt.....................77 Nzm (57 ft. lbs.)
Pinion Nut...............292-427 Nzm (215-315 ft. lbs.)
Ring Gear Bolt.............95-122 Nzm (70-90 ft. lbs.)
RWAL/ABS Sensor Bolt.........24 Nzm (18. ft. lbs.)
8 1/4 AXLE
DESCRIPTION ................................................TORQUE
Diff. Cover Bolt........................47 Nzm (35 ft. lbs.)
Bearing Cap Bolt.....................95 Nzm (70 ft. lbs.)
Pinion Nut.............................285 Nzm (210 ft. lbs.)
Ring Gear Bolt.........................95 Nzm (70 ft. lbs.)
RWAL/ABS Sensor Bolt.........24 Nzm (18. ft. lbs.)
JREAR SUSPENSION AND AXLES 3 - 51

Page 137 of 2198

Page 138 of 2198

BRAKES
CONTENTS
page page
ABS BRAKE DIAGNOSIS................... 3
ABS OPERATION AND SERVICE............ 33
BRAKE FLUIDÐBRAKE BLEEDINGÐ
BRAKELINES AND HOSES............... 10
DISC BRAKES.......................... 45
DRUM BRAKES......................... 55
GENERAL INFORMATION.................. 1MASTER CYLINDERÐCOMBINATION VALVE . . 15
PARKING BRAKES....................... 60
POWER BRAKE BOOSTERÐBRAKE PEDALÐ
BRAKELIGHT SWITCH.................. 22
SERVICE BRAKE DIAGNOSIS............... 4
SPECIFICATIONS........................ 70
GENERAL INFORMATION
INDEX
page page
Antilock Brakes (ABS)....................... 1
Brake Components......................... 1
Brake Fluid/Lubricants/Cleaning Solvents......... 2
Brake Safety Precautions.................... 2Brake Warning Lights....................... 1
Brakelining Material........................ 1
Jeep Body Code Letters..................... 2
BRAKE COMPONENTS
Power assist front disc and rear drum brakes are
standard on Cherokee/Wrangler models. Disc brake
components consist of single piston calipers and ven-
tilated 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 foot pedal on YJ models and
a hand lever on XJ models.
A 205 mm dual diaphragm vacuum power brake
booster is used for all applications. Two master cylin-
ders are used; 4-cylinder YJ models have a one-piece
master cylinder. All other models have a two-piece
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.
BRAKELINING MATERIAL
Factory brakelining on all models consists of an or-
ganic base material combined with metallic particles.
The lining does not contain asbestos.
BRAKE WARNING LIGHTS
Cherokee/Wrangler models are equipped with one
or two brake warning lights. A red warning light is
standard on all models. An amber light is added on
models with ABS brakes. Both lights are located in
the instrument panel.
The red light is in circuit with the pressure differ-
ential switch (in the combination valve), and with the
parking brake switch. The light alerts the driver
when the parking brakes are applied, or when a
pressure differential exists between the front and
rear hydraulic systems. The light also illuminates for
a few seconds at start up as part of a bulb check.
The ABS warning light is amber in color and is lo-
cated in the same side of the instrument cluster as
the red warning light. The amber light only illumi-
nates when an ABS circuit fault occurs.
ANTILOCK BRAKES (ABS)
An antilock brake system (ABS) is available on
Cherokee/Wrangler models as an option. The system
is an electronically operated, all-wheel brake control
system. The ABS system is designed to prevent
wheel lockup during periods of high wheel slip brak-
ing. Refer to the antilock brake section for operation
and service information.
JBRAKES 5 - 1

Page 139 of 2198

ABS SYSTEM CHANGES
A different master cylinder, power brake booster,
and HCU are used in the 1995 Jeep ABS system.
The master cylinder reservoir has a single filler cap
and is no longer interconnected with the HCU. The
new HCU has built-in accumulators. The pedal travel
sensor has been eliminated and a new dual dia-
phragm power brake booster is used.
BRAKE FLUID/LUBRICANTS/CLEANING SOLVENTS
Recommended fluid for all Jeep vehicles is Mopar
DOT 3 brake fluid, or an equivalent meeting SAE
J1703 and DOT 3 standards.
Use Mopar Multi Mileage grease to lubricate drum
brake pivot pins and rear brakeshoe contact points
on the support plates. Use GE 661, or Dow 111 sili-
cone grease on caliper bushings and mounting bolts.
Use fresh brake fluid or Mopar brake cleaner to
clean or flush brake system components. These are
the only cleaning materials recommended.
CAUTION: Never use gasoline, kerosene, methyl or
isopropyl alcohol, paint thinner, or any fluid con-
taining mineral oil to clean brake parts. These fluids
damage rubber cups and seals. If system contami-
nation is suspected, check the fluid for dirt, discol-
oration, or separation into distinct layers. Drain and
flush the system with new brake fluid if contamina-
tion is suspected.
JEEP BODY CODE LETTERS
The body/model identification code letters for Jeep
vehicles are as follows:²Code letters XJ: Cherokee
²Code letters YJ: Wrangler/YJ
The code letters are used throughout this group to
simplify model identification and component applica-
tion.
BRAKE SAFETY PRECAUTIONS
WARNING: ALTHOUGH FACTORY INSTALLED
BRAKELINING ON JEEP VEHICLES IS MADE FROM
ASBESTOS FREE MATERIALS, SOME AFTER MAR-
KET BRAKELINING MAY CONTAIN ASBESTOS. THIS
SHOULD BE TAKEN INTO ACCOUNT WHEN RE-
PAIRING A VEHICLE WITH PRIOR BRAKE SERVICE.
WEAR A RESPIRATOR WHEN CLEANING BRAKE
COMPONENTS AS ASBESTOS FIBERS CAN BE A
HEALTH HAZARD. NEVER CLEAN WHEEL BRAKE
COMPONENTS WITH COMPRESSED AIR. USE A
VACUUM CLEANER SPECIFICALLY DESIGNED FOR
REMOVING BRAKE DUST. IF A VACUUM CLEANER
IS NOT AVAILABLE, CLEAN THE PARTS WITH WA-
TER DAMPENED SHOP RAGS. DO NOT CREATE
DUST BY SANDING BRAKELINING. DISPOSE OF
ALL DUST AND DIRT SUSPECTED OF CONTAINING
ASBESTOS FIBERS IN SEALED BAGS OR CON-
TAINERS. FOLLOW ALL SAFETY PRACTICES REC-
OMMENDED BY THE OCCUPATIONAL SAFETY AND
HEALTH ADMINISTRATION (OSHA) AND THE ENVI-
RONMENTAL PROTECTION AGENCY (EPA), FOR
HANDLING AND DISPOSAL OF ASBESTOS.
5 - 2 BRAKESJ

Page 140 of 2198

ABS BRAKE DIAGNOSIS
INDEX
page page
ABS Diagnostic Connector................... 3
ABS Warning Light Display................... 3
Antilock ECU and Hcu Diagnosis............... 3
DRB Scan Tool............................ 3General Information........................ 3
Normal Operating Conditions.................. 3
Wheel/Tire Size and Input Signals.............. 3
GENERAL INFORMATION
The DRB scan tool is required for ABS diagnosis.
The scan tool is used to identify ABS circuit faults.
Once a faulty circuit has been identified, refer to
the appropriate chassis/body diagnostic manual for
individual component testing.
ABS WARNING LIGHT DISPLAY
The amber antilock light illuminates at startup as
part of the system self check feature. The light illu-
minates for 2-3 seconds then goes off as part of the
normal check routine.
An ABS circuit fault is indicated when the amber
light remains on after startup, or illuminates during
vehicle operation.
Verify that a fault is actually related to the ABS
system before making repairs. For example, if the
red warning illuminates but the ABS light does not,
the problem is related to a service brake component
and not the ABS system. Or, if neither light illumi-
nates but a brake problem is noted, again, the prob-
lem is with a service brake component and not with
the ABS system.
ABS DIAGNOSTIC CONNECTOR
The ABS diagnostic connector is inside the vehicle.
The connector is the access point for the DRB scan tool.
On XJ models, the connector is located under the
instrument panel to the right of the steering column.
On some models, the connecter may be tucked under
the carpeting on the transmission tunnel. The con-
necter is a black, 6-way type.
On YJ models, the connector is under the instru-
ment panel by the the driver side kick panel. The
connecter is a black, 6 or 8-way type.
The DRB scan tool kit contains adapter cords for
both types of connecter. Use the appropriate cord for
test hookup.
DRB SCAN TOOL
ABS diagnosis is performed with the DRB scan tool.
Refer to the DRB scan tool manual for test hookup and
procedures. Diagnosis information is provided in the ap-
propriate chassis/body diagnostic manual.
WHEEL/TIRE SIZE AND INPUT SIGNALS
Antilock system operation is dependant on accurate
signals from the wheel speed sensors. Ideally, the ve-
hicle wheels and tires should all be the same size
and type. However, the Jeep ABS system is designed
to operate with a compact spare tire installed.
NORMAL OPERATING CONDITIONS
Sound Levels
The hydraulic control unit pump and solenoid valves
may produce some sound as they cycle on and off. This
is a normal condition and should not be mistaken for
faulty operation. Under most conditions, pump and so-
lenoid valve operating sounds will not be audible.
Vehicle Response In Antilock Mode
During antilock braking, the hydraulic control unit
solenoid valves cycle rapidly in response to antilock
electronic control unit signals.
The driver will experience a pulsing sensation
within the vehicle as the solenoids decrease, hold, or
increase pressure as needed. Brake pedal pulsing will
also be noted and is anormal condition.
Steering Response
A modest amount of steering input is required dur-
ing extremely high deceleration braking, or when
braking on differing traction surfaces. An example of
differing traction surfaces would be when the left
side wheels are on ice and the right side wheels are
on dry pavement.
Owner Induced Faults
Driving away with the parking brakes still applied
will cause warning light illumination. Pumping the
brake pedal will also generate a system fault and in-
terfere with ABS system operation.
ANTILOCK ECU AND HCU DIAGNOSIS
An ECU or HCU fault can only be determined
through testing with the DRB scan tool. Do not re-
place either component unless a fault is actually in-
dicated.
JABS BRAKE DIAGNOSIS 5 - 3

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