1988 JEEP CHEROKEE lock

(1) - This condition may be normal on some vehicles equipped with
anti-lock brakes.
( 2) - Refer to OEM procedures for adjusting low fluid level.
Inspect for brake hydraulic system leaks and friction
material wear.
( 3) - This condition may indicate contaminated brake fluid.
See BRAKE FLUID .









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MODULATORS
See HYDRAULIC MODULATORS .
MOTORS
See ELECTRICAL PUMPS AND MOTORS .
PARKING BRAKE SWITCHES
See SWITCHES.
PARKING BRAKE SYSTEMS
NOTE: The parking brake is an integral part of the brake
system. It is important that the parking brake function
properly when brake service is performed.
PARKING BRAKE SYSTEM INSPECTION









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Condition Code Procedure
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.
Attaching hardware
missing ................ C .......... Require replacement of
hardware.
Attaching hardware not
functioning ............ A ... Require repair or replacement
of hardware.
Cable improperly
adjusted ............... B ....... Require cable adjustment.
Cable or individual
wires in the cable
are broken ............. A .... Require replacement of cable
assembly.
Cable sticking .......... A ...... Require cable lubrication.
Cable stuck inside conduit
and cannot be lubricated
so that parking brake
functions properly ..... A .... Require replacement of cable
assembly.
Inoperative ( 1) ......... A .......... Require replacement of
inoperative parts.
Parking brake
parts bent ............. B ... Require repair or replacement
of bent parts.
Parking brake
parts broken ........... A ... Require replacement of broken
parts.
Parking brake parts

Terminal burned, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal corroded,
affecting performance .. A .. Require repair or replacement.
Terminal corroded, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal loose, affecting
performance ............ B .. Require repair or replacement.
Terminal loose, not
affecting performance .. 1 .. Suggest repair or replacement.
(1) - Inoperative includes intermittent operation or out of OEM
specification.
( 2) - Determine cause and correct prior to repair or
replacement of part.









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ROTORS
Determine the need to recondition based upon individual rotor
conditions that follow. Friction material replacement does not require
rotor reconditioning unless other justifications exist. DO NOT
recondition new rotors unless they are being pressed or bolted onto an
existing hub. It is not necessary to replace rotors in axle sets.
However, when replacing or reconditioning a rotor due to the
conditions that follow, you may suggest reconditioning of the other
rotor on the same axle to eliminate uneven braking behavior.
Determine the need to replace based upon the individual rotor
conditions that follow. Reconditioning is defined as machining and
block sanding, or block sanding only. Block sanding is defined as
using 120-150 grit sandpaper with moderate to heavy force for 60
seconds per side. Always wash rotors after servicing or before
installing.
ROTOR INSPECTION









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Condition Code Procedure
Corrosion affecting
structural integrity ... A ........ ( 1) Require replacement.
Cracked ................. B ............ Require replacement.
Hard spots .............. 2 ....... Suggest reconditioning or
replacement of rotor according
to OEM specifications.
Lateral runout (wobble)
exceeds OEM
specifications ......... B ............ Require re-indexing,
reconditioning, or replacement
according to specifications.
Measured thickness is less
than OEM discard
specifications ......... B ............ Require replacement.
Rotor thickness is less
than OEM "machine to"
specifications but thicker
than "discard at"
specifications, and the
rotor does not require
reconditioning ......... 1 ........ ( 2) Suggest replacement.
Rotor thickness will be
less than OEM "machine to"
specifications after
required

and reinstalled. Brake shoes can be manually adjusted by rotating
adjuster screw. Remove access slot cover.
3) Using a small blade screwdriver, push in on adjustment
lever to separate from adjustment screw. Turn adjustment screw until
brake drum is locked tight. Back screw off until wheel rotates freely.
If brake drum is to be removed, back off adjustment screw several
notches for adequate clearance.
HEIGHT SENSING PROPORTIONING VALVE - COMANCHE
NOTE: Anytime adjustment is required the lever bushing must be
replaced.
Adjustment must be made on a drive-on lift or a flat level
surface with vehicle at curb weight. Remove height sensing
proportioning valve shaft nut and washer. Disconnect valve lever and
remove spring. Remove and discard bushing.
Rotate valve shaft to permit installation and proper
alignment of valve adjusting gauge (J-35853-2).
NOTE: The gauge (J-35853-2) must be properly seated on the "D"
shape of the shaft and the lower mounting bolt of the valve.
See Fig. 2. Also, all linkage components, excluding the
spring, must be connected to the axle housing before
installation of bushing.
Place lever bushing in lever. Using bushing installation
tool (J-35853-1) press bushing along with lever onto valve shaft.
Remove lever and adjusting to (J-35853-2) then install the spring.
Install lever, washer and retaining nut. Tighten retaining nut to 100
Inch-lbs. (11 N.m). Connect spring to lever arm.
Fig. 1: Exploded View of Height Sensing Proportioning Valve

1) Adjust rear brakes. Check cable for binds, kinks or frayed
condition. Replace cable (if necessary). Release parking brake. Loosen\
lock nuts at parking brake cable equalizer under vehicle.
2) Tighten cables until wheels drag slightly when rotated by
hand. Loosen equalizer until wheels rotate freely and no drag is felt.
Tighten lock nuts and check operation of parking brake.
ROTOR SERVICING
RUNOUT
1) Measure rotor lateral runout by mounting a dial indicator
on support stand or steering spindle. Position indicator stylus so it
contacts center of rotor braking surface.
2) Zero indicator and turn rotor one revolution. Note
indicator reading. Runout must not exceed specification. See DISC
BRAKE ROTOR SPECIFICATIONS table. Refinish or replace rotor (if
necessary).
NOTE: Thickness of machined rotor must not be below minimum
thickness specification.
PARALLELISM
Measure rotor parallelism with a micrometer. Measure
thickness at 4 or more equally spaced points around rotor at
approximately 1" from edge of rotor. Variation must not exceed
specification. See DISC BRAKE ROTOR SPECIFICATIONS table. Refinish or
replace rotor (if necessary).
BRAKE SYSTEM BLEEDING
Hydraulic system bleeding is necessary any time air has been
introduced into system. Bleed brakes at all 4 wheels if master
cylinder lines have been disconnected or master cylinder has run dry.
Bleed brakes with vacuum bleeding equipment, pressure bleeding
equipment or by manually pumping brake pedal while using bleeder
tubes. Always bleed brake lines in sequence. See BLEEDING SEQUENCE
table.
MASTER CYLINDER BLEEDING
Bench Bleeding
1) Master cylinder must be bled before installation to
prevent excessive amounts of air from entering the brake system,
creating poor brake operation.
2) Place master cylinder in soft-jawed vise. DO NOT tighten
vise enough to damage master cylinder. Install bleeder tubes in both
outlets of master cylinder. See Fig. 5.

Clean hub and rotor mating surfaces. To install, reverse
removal procedure.
NOTE: DO NOT disconnect brake hose from caliper unless caliper is
to be disassembled.
DISC BRAKE ROTOR - CHEROKEE, COMANCHE & WAGONEER
Removal
1) Raise and support vehicle. Remove front wheel and caliper.
Suspend caliper from frame or suspension. Remove cap, cotter pin, nut
retainer, adjusting nut and thrust washer from spindle.
2) Remove outer bearing from hub. Remove hub and rotor from
spindle. Remove hub and rotor seal. Remove inner bearing from hub.
Installation
1) Apply small amount of "EP" type waterproof wheel bearing
grease in hub cavity. Lubricate inner and outer bearings. Install
inner bearing and seal in rotor. Clean rotor surface (if necessary).
2) Install hub and rotor on spindle. Install outer bearing,
thrust washer and spindle nut. Tighten spindle nut to 17-25 ft. lbs.
(23-34 N.m) while rotating rotor to seat bearings. Loosen spindle nut
1/2 a turn and retighten an additional 19 INCH lbs (2 N.m). Reverse
removal procedure to complete installation.
DISC BRAKE ROTOR - GRAND WAGONEER
Removal
1) Raise vehicle and support with safety stands. Remove wheel
and caliper. On models without front hubs, remove rotor hub cap, drive
gear snap ring, drive gear, pressure spring and spring cup.
2) On models with front hubs, remove screws attaching hub
body to hub clutch and remove hub body from clutch. Remove large and
small retaining rings. Remove hub clutch from axle shaft.
3) On all models, remove wheel bearing outer and inner lock
nuts and retaining ring using Socket (J-6893-D). Remove rotor. Remove
wheel bearings from rotor.
Installation
1) Lubricate bearings with "EP" type waterproof wheel bearing
grease. Install bearings and seal in rotor. Install rotor and inner
lock nut. Inner lock nut has a locating peg on one side. When
installed, peg must face away from bearing.
2) Install wheel, but do not tighten lug nuts completely.
Tighten inner lock nut to 50 ft. lbs. (68 N.m) while rotating wheel.
Back of inner lock nut 1/6 turn (45-65 degrees).
3) Install retaining washer. Ensure that inner lock nut
locating peg is engaged with retaining washer. Install outer lock nut
and tighten to 50 ft. lbs. (68 N.m).
4) On models without front hubs, install pressure spring cup,
pressure spring, drive gear and snap ring. Coat rim of chrome hub
cover with Permatex No. 3 and install cap in rotor hub.
NOTE: Recessed side of spring cup faces outer bearing and flat
side faces pressure spring.
5) On models with front hubs, install hub clutch on axle.
Install large and small hub retaining rings. Install hub body on
clutch and tighten to 30 INCH lbs. (3 N.m). Reverse removal procedure
to complete installation.
DRUM BRAKE SHOES - EXCEPT GRAND WAGONEER

CLU TC H

1988 J e ep C hero ke e
1988 Clutch
Hydraulic
Cherokee, Comanche, Wagoneer, Wrangler
DESCRIPTION
The clutch assembly consists of a single dry-disc driven
plate and a one-piece diaphragm spring-type clutch cover. On Wrangler
4-cylinder models, the clutch cover and driven plate diameter is 9.28"
(232 mm). On Wrangler 6-cylinder models, the clutch cover and driven
plate diameter is 10.5" (266 mm). On all other 4 and 6-cylinder
models, the clutch cover and driven plate diameter is 9.7"
(246 mm). The clutch is actuated through a hydraulic master cylinder
and slave cylinder.
On Wrangler models, the slave cylinder is mounted inside the
clutch housing. The bearing is permanently attached to the cylinder
piston.
TRANSMISSION APPLICATION









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Vehicle Model Transmission Model
Cherokee, Comanche, Wagoneer ........... Aisin AX4 4-Speed
Aisin AX5 5-Speed O/D
Wrangler ........................... Aisin AX5 5-Speed O/D
Peugeot BA 10/5 5-Speed O/D









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REMOVAL & INSTALLATION
TRANSMISSION
Removal
1) Remove the shift knob and lock nut from transmission and
transfer case shift levers (if equipped). On Wrangler models, remove
screws attaching transmission and transfer case shift lever boots and
remove both boots.
2) On all other models, raise outer gearshift lever boot and
remove upper part on center console. Remove lower part of console,
remove inner boot and gearshift lever.
3) On Wrangler models, remove transmission shift tower dust
cover. Remove transmission shift lever and stub shaft. DO NOT remove
shift lever from stub shaft.
4) On all models, raise and support vehicle. Drain
transmission lubricant. Mark rear drive shaft for reassembly and
remove rear drive shaft. Support transmission assembly and remove
crossmember. Disconnect speedometer cable and wiring from back-up
light switch.
5) On 4WD models, drain transfer case lubricant. Disconnect
transfer case vacuum hoses and linkage. Tag vacuum hoses for
reassembly. Disconnect front drive shaft and secure out of way.
6) On all models, remove clutch slave cylinder. Position
transmission jack under transmission assembly. Remove bolts securing
clutch housing to engine and remove transmission assembly. Remove
throw-out lever, bearing, and pivot ball from clutch housing.
Installation
To install, reverse removal procedure.

Removal (Cherokee, Comanche & Wagoneer)
Remove clutch assembly. Remove pilot bushing using Slide
Hammer (J-2619-01) and Bushing Remover (J-5822).
Installation
Lubricate replacement bushing with engine oil. Remove pilot
bushing lubricating wick and soak wick in engine oil. Install wick in
bushing bore. Install bushing using Clutch Pilot Shaft (J-33169). Keep\
pilot shaft parallel with crankshaft center line to prevent damage to
bushing. Reverse removal procedure to complete installation.
OVERHAUL
CLUTCH MASTER CYLINDER
Disassembly
1) Remove reservoir cap and cover. Remove push rod dust
cover. Remove snap ring holding push rod in cylinder bore. Discard
dust cover and snap ring.
2) Remove push rod, retaining washer, and seal as an
assembly. Discard seal. Remove plunger, valve spring, and valve stem
assembly from cylinder bore by tapping cylinder body on wood block.
3) Compress valve spring slightly. Pry tab of valve stem
retainer upward to release retainer, spring and stem assembly from
plunger. Remove seal from plunger and discard. Remove spring retainer
and valve stem from valve spring.
NOTE: Retainer tab is located in rectangular slot in side of stem
retainer.
4) Remove valve stem from retainer. Remove spring washer and
stem tip seal from end of valve stem. See Fig. 3. Discard stem tip
seal and spring washer. Clean parts with brake fluid or brake cleaning
solvent.
5) Inspect cylinder bore for wear, nicks or scores. Master
cylinder bore must be clean and smooth. Light discoloration is
acceptable. Replace if necessary. Clutch master cylinder must not be
honed under any circumstances.
Fig. 3: Exploded View Of Clutch Master Cylinder
Courtesy of Chrysler Motors.
Reassembly
1) Lubricate cylinder bore with brake fluid. Make sure lip of

plunger seal faces stem end of plunger. Install stem tip seal so seal
shoulder fits in undercut at end of valve stem.
2) End of valve stem should pass through stem retainer and
seat in small bore in end of plunger. Bend retainer tab downward to
lock stem and retainer on plunger. To complete assembly, reverse
disassembly procedures.
CLUTCH SLAVE CYLINDER
Disassembly
NOTE: On Wrangler models, the integral slave cylinder and throw
out bearing assembly is not serviceable. If cylinder,
bearing or lines become damaged the entire assembly must be
replaced.
1) Clean cylinder exterior. Remove dust boot from cylinder.
Remove cylinder push rod, plunger and spring as an assembly. Remove
spring seal from plunger.
2) Remove snap ring holding push rod in plunger. Remove push
rod and boot. Remove boot from push rod. See Fig. 4. Clean parts with
brake fluid or brake cleaning solvent. Inspect cylinder bore for wear,
nicks or scores. Replace if necessary.
Fig. 4: Exploded View Of Clutch Slave Cylinder
Courtesy of Chrysler Motors.
Reassembly
Reverse disassembly procedure. Lubricate cylinder bore and
seal with brake fluid before reassembly.
HYDRAULIC SYSTEM BLEEDING
1) Fill master cylinder reservoir with DOT 3 brake fluid. On
all models except Wrangler, compress slave cylinder plunger by pushing
release lever as far forward as possible.
2) Attach rubber hose to slave cylinder bleeder screw.
Immerse other end of hose in glass container 1/2 full of brake fluid.
Loosen bleeder screw and have an assistant depress clutch pedal.
Tighten bleeder screw and release pedal.
3) Repeat bleeding procedure until fluid entering container
is free of bubbles. DO NOT allow reservoir to run out of fluid during