\003
* B RAK E S YSTE M U NIF O RM IN SPEC TIO N G UID ELIN ES *
1 988 J e ep C hero ke e
GENERAL INFORMATION
Brake Systems - Motorist Assurance Program
Standards For Automotive Repair
All Makes & Models
CONTENTS
OVERVIEW OF MOTORIST ASSURANCE PROGRAM
OVERVIEW OF SERVICE REQUIREMENTS AND SUGGESTIONS
ACCELEROMETERS (G SENSOR OR LATERAL)
ACCUMULATORS
ANCHOR PINS
ANTI-LOCK BRAKE SYSTEMS
BACKING PLATES
BRAKE FLUID
BRAKE FRICTION MATERIAL
BRAKE PADS
BRAKE PEDALS
BRAKE SHOES
BRAKE SHOE HARDWARE
BRAKE STOPLIGHT SWITCHES
BULB SOCKETS
BULBS AND LEDS
CALIPER HARDWARE
CALIPERS
CONTROLLERS
DIGITAL RATIO AXLE CONTROLLERS AND BUFFERS (DRAC AND DRAB)
DISABLE SWITCHES
DRUMS
ELECTRICAL PUMPS AND MOTORS
ELECTRONIC CONTROLLERS
FLUID
FLUID LEVEL SENSOR SWITCHES
FOUR WHEEL DRIVE SWITCHES
FRICTION MATERIAL
G SENSORS
HOSES
HYDRAULIC MODULATORS
HYDRO-BOOSTERS
HYDRO-ELECTRIC BOOSTERS (POWERMASTER)
IGNITION DISABLE SWITCHES
LATERAL ACCELERATION SWITCHES
LEDS
LENSES
MASTER CYLINDERS
MODULATORS
MOTORS
PARKING BRAKE SWITCHES
PARKING BRAKE SYSTEMS
PADS
PEDAL TRAVEL SWITCHES
PEDALS
POWERMASTER
PUMPS
PRESSURE DIFFERENTIAL SWITCHES
PRESSURE SWITCHES
RELAYS
ROTORS
SELF-ADJUSTING SYSTEMS
system which DOES NOT affect the rubber parts, the required
service is to flush and fill with the correct brake fluid.
(Code B)
( 2) - This condition may indicate contaminated brake fluid.
\
\
\
\
\
\
\
BRAKE FRICTION MATERIAL
See FRICTION MATERIAL .
BRAKE PADS
See FRICTION MATERIAL .
BRAKE PEDALS
BRAKE PEDAL INSPECTION \
\
\
\
\
\
\
Condition Code Procedure
Bent, affecting
performance ............ A .. Require repair or replacement.
Broken .................. A .. Require repair or replacement.
Pedal pad missing ....... C .... Require replacement of pedal
pad.
Pedal pad worn .......... 1 ............ Suggest replacement.
Pivot bushings worn,
affecting performance .. A .... Require replacement of pivot
bushings.
\
\
\
\
\
\
\
BRAKE SHOES
See FRICTION MATERIAL .
BRAKE SHOE HARDWARE
See also SELF-ADJUSTING SYSTEMS .
BRAKE SHOE HARDWARE INSPECTION
\
\
\
\
\
\
\
Condition Code Procedure
Broken .................. A ............ Require replacement.
Distorted ............... A ............ Require replacement.
Missing ................. C ............ Require replacement.
Surfaces rust-pitted .... 1 ............ Suggest replacement.
Worn, affecting
performance ............ A ............ Require replacement.
\
\
\
\
\
\
\
BRAKE STOPLIGHT SWITCHES
BRAKE STOPLIGHT INSPECTION \
\
\
\
\
\
\
Condition Code Procedure
Bent .................... B ............ Require replacement.
Broken .................. A ............ Require replacement.
Connector broken ........ A .. Require repair or replacement.
Connector (Weatherpack
type) leaking .......... A .. Require repair or replacement.
missing ................ C .. Require replacement of missing
parts.
Threads damaged ......... A .. Require repair or replacement.
Threads stripped (threads
missing) ............... A ............ Require replacement.
(1) - Inoperative includes intermittent operation.
\
\
\
\
\
\
\
PADS
See FRICTION MATERIAL .
PEDAL TRAVEL SWITCHES
See SWITCHES.
PEDALS
See BRAKE PEDALS.
POWERMASTER
See HYDRO-BOOSTERS .
PUMPS
See ELECTRICAL PUMPS AND MOTORS .
PRESSURE DIFFERENTIAL SWITCHES
See SWITCHES.
PRESSURE SWITCHES
See SWITCHES.
RELAYS
NOTE: Copied from Electrical UIGs
RELAY INSPECTION
\
\
\
\
\
\
\
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.
Housing broken .......... A ............ Require replacement.
Housing cracked ......... 2 ............ Suggest replacement.
Inoperative ( 1) ......... A ............ Require replacement.
Missing ................. C ............ Require replacement.
Terminal broken ......... A .. Require repair or replacement.
Terminal burned,
affecting performance .. A ........... ( 2) Require repair or
replacement.
BRAK E S YSTE M
1988 J e ep C hero ke e
1988 BRAKES
Jeep - Brake System
Cherokee, Comanche, Grand Wagoneer, Wagoneer, Wrangler
DESCRIPTION
DISC BRAKES
Floating caliper disc brake assembly uses a single piston
caliper which "floats" on 2 bolts. As brake pedal is depressed,
hydraulic pressure is passed through a proportioning valve to brake
caliper piston.
This force is transmitted to inboard brake pad, forcing it
against braking surface of rotor. Pressure then moves outer caliper
housing and pad inward on caliper mounting bolts, thus forcing outer
pad against outer braking surface of rotor.
DRUM BRAKES
Self-centering type system uses primary and secondary brake
shoes with cable operated automatic adjusters. Brake shoe anchor is
located at upper end of shoes above wheel cylinder. Single double
acting brake cylinder is used.
MASTER CYLINDER - EXCEPT GRAND WAGONEER
The Delco Quick Take-Up master cylinder is used with systems
utilizing low drag calipers. Master cylinder includes a quick take-up
valve which delivers a large volume of fluid, at low pressure, upon
initial brake application.
MASTER CYLINDER - GRAND WAGONEER
Bendix and Delco-Moraine tandem dual piston master cylinders
are single casting type with front and rear pistons and a separate
reservoir and outlet for each piston. Primary piston is operated by
push rod connected to brake pedal. Secondary piston is operated by
primary piston.
ADJUSTMENTS
NOTE: For Hub, Bearing and Axle Shaft Removal, Installation and
Adjustment information, see appropriate DRIVE AXLES article.
DISC BRAKE PADS
Automatic adjustment is provided by outward relocation of
piston as lining wears.
DRUM BRAKE SHOES
1) Rear brake shoes adjust automatically as brakes are
applied while vehicle is operated in reverse. Drive vehicle in reverse
applying brakes firmly 10-15 times, between each reverse brake
application, drive vehicle forward and press brakes firmly.
2) Manual adjustment is required if shoes have been removed
Before bleeding system, exhaust all vacuum from power unit by
depressing brake pedal several times. Bleed master cylinder (if
equipped) with bleeder screws. Bleed slave cylinder on vehicles
equipped with remote mount power assist units. Bleed wheel cylinders
and calipers in sequence. See BLEEDING SEQUENCE table.
BLEEDING SEQUENCE TABLE
\
\
\
\
\
\
Application Sequence
All Models ................................ RR, LR, RF, LF
\
\
\
\
\
\
REMOVAL & INSTALLATION
DISC BRAKE CALIPER
Removal & Installation
Caliper removal and installation procedures are same as for
disc pad replacement. To remove caliper from vehicle, disconnect brake
line at caliper and cap hole to prevent contamination.
DISC BRAKE PADS
Removal
1) Drain 2/3 of brake fluid from master cylinder reservoir.
Raise vehicle and support with safety stands. Remove front wheel
assembly.
2) Place "C" clamp on caliper. Solid end of clamp should
contact back of caliper. Screw end should contact metal part of
outboard shoes.
3) Tighten "C" clamp until caliper forces piston to bottom of
bore. Remove both Allen head mounting bolts and lift caliper off
rotor. Support caliper out of the way.
4) On Grand Wagoneer, remove both brake pads from caliper.
Note spring position and support spring from inboard shoe. Remove
sleeves and bushings from caliper.
5) On all other models, hold anti-rattle clip against caliper
adapter and remove outer brake pad. Remove inner brake pad and anti-
rattle clip from caliper adapter.
Installation
1) To install, reverse removal procedure. On Grand Wagoneer,
lubricate new bushings, sleeves, bushing grooves, and small ends of
mounting bolts with silicone lubricant. Install rubber bushings in
caliper mounting ears.
2) On all other models, clean caliper mating surfaces on
adapter with a wire brush. Apply double sided adhesive tape to back
side of inner pad. Clean caliper piston surface. Lubricate caliper
mating surfaces on caliper adapter.
3) On all models, lubricate caliper mounting bolts using
brake corrosion lubricant and tighten mounting bolts. Add brake fluid
to reservoir. Apply brakes until brake pedal is firm. Check brake
fluid level.
DISC BRAKE ROTOR - WRANGLER
Removal
Raise and support vehicle. Remove front wheel and caliper.
Suspend caliper from frame or suspension. Remove rotor from hub.
Installation