wheel JEEP LIBERTY 2002 KJ / 1.G Manual PDF

Examine the lining contact pattern to determine if
the shoes are bent or the drum is tapered. The lining
should exhibit contact across its entire width. Shoes
exhibiting contact only on one side should be
replaced and the drum checked for runout or taper.
Inspect the adjuster screw assembly. Replace the
assembly if the star wheel or threads are damaged,
or the components are severely rusted or corroded.
Discard the brake springs and retainer components
if worn, distorted or collapsed. Also replace the
springs if a brake drag condition had occurred. Over-
heating will distort and weaken the springs.
Inspect the brake shoe contact pads on the support
plate, replace the support plate if any of the pads are
worn or rusted through. Also replace the plate if it is
bent or distorted.
(1) Clean support plate with brake cleaner.
(2) If new drums are being installed, remove pro-
tective coating with carburetor cleaner followed by
final rinse with brake cleaner.
(3) Clean and lubricate anchor pin with light coat
of Mopar multi-mileage grease.
(4) Apply Mopar multi-mileage grease to brake
shoe contact surfaces of support plate (Fig. 10).
(5) Lubricate the adjuster screw threads and pivot
with spray lube.
(6) Attach parking brake lever to secondary brake
shoe. Use new washer and U-clip to secure lever.
(7) Attach the parking brake cable to lever (if
removed).
(8) Install the brake shoes on support plate.
Secure shoes with new hold-down springs, pins and
retainers.
(9) Install the parking brake strut and spring.(10) Install the guide plate and adjuster cable on
anchor pin.
(11) Install the adjuster cable guide on the shoe.
(12) Install the primary and secondary return
springs.
(13) Lubricate and assemble adjuster screw.
(14) Install the adjuster screw, spring and lever
and connect to adjuster cable.
(15) Adjust the shoes to the drum (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/BRAKE
PADS/SHOES - ADJUSTMENTS).
(16) Install the brake drum.
(17) Install the wheel/tire assemblies and lower
vehicle (Refer to 22 - TIRES/WHEELS/WHEELS -
STANDARD PROCEDURE).
(18) Verify firm brake pedal before moving vehicle.
ADJUSTMENTS
ADJUSTMENT - REAR DRUM BRAKE
The rear drum brakes are equipped with a self-ad-
justing mechanism. Under normal circumstances, the
only time adjustment is required is when the shoes
are replaced, removed for access to other parts, or
when one or both drums are replaced.
Adjustment can be made with a standard brake
gauge or with adjusting tool. Adjustment is per-
formed with the complete brake assembly installed
on the backing plate.
ADJUSTMENT WITH BRAKE GAUGE
(1) Be sure parking brakes are fully released.
(2) Raise rear of vehicle and remove wheels and
brake drums.
(3) Verify that left and right automatic adjuster
levers and cables are properly connected.
(4) Insert brake gauge in drum. Expand gauge
until gauge inner legs contact drum braking surface.
Then lock gauge in position (Fig. 11).
(5) Reverse gauge and install it on brake shoes.
Position gauge legs at shoe centers as shown (Fig.
12). If gauge does not fit (too loose/too tight), adjust
shoes.
(6) Pull shoe adjuster lever away from adjuster
screw star wheel.
(7) Turn adjuster screw star wheel (by hand) to
expand or retract brake shoes. Continue adjustment
until gauge outside legs are light drag-fit or 30 thou-
sands of an inch clearence on the shoes.
(8) Install brake drums and wheels and lower
vehicle.
(9) Drive vehicle and make one forward stop fol-
lowed by one reverse stop. Repeat procedure 8-10
times to operate automatic adjusters and equalize
adjustment.
Fig. 10 Shoe Contact Surfaces
1 - ANCHOR PIN
2 - SUPPORT PLATE
3 - SHOE CONTACT SURFACES
5 - 12 BRAKES - BASEKJ
BRAKE PADS / SHOES (Continued)

NOTE: Bring vehicle to complete standstill at each
stop. Incomplete, rolling stops will not activate
automatic adjusters.
ADJUSTMENT WITH ADJUSTING TOOL
(1) Be sure parking brake lever is fully released.
(2) Raise vehicle so rear wheels can be rotated
freely.
(3) Remove plug from each access hole in brake
support plates.
(4) Loosen parking brake cable adjustment nut
until there is slack in front cable.
(5) Insert adjusting tool through support plate
access hole and engage tool in teeth of adjusting
screw star wheel (Fig. 13).(6) Rotate adjuster screw star wheel (move tool
handle upward) until slight drag can be felt when
wheel is rotated.
(7) Push and hold adjuster lever away from star
wheel with thin screwdriver.
(8) Back off adjuster screw star wheel until brake
drag is eliminated.
(9) Repeat adjustment at opposite wheel. Be sure
adjustment is equal at both wheels.
(10) Install support plate access hole plugs.
(11) Adjust parking brake cable and lower vehicle.
(12) Drive vehicle and make one forward stop fol-
lowed by one reverse stop. Repeat procedure 8-10
times to operate automatic adjusters and equalize
adjustment.
NOTE: Bring vehicle to complete standstill at each
stop. Incomplete, rolling stops will not activate
automatic adjusters.DISC BRAKE CALIPERS
DESCRIPTION
The calipers are a single piston type. The calipers
are free to slide laterally, this allows continuous com-
pensation for lining wear.
Fig. 11 ADJUSTING GAUGE ON DRUM
1 - BRAKE GAUGE
2 - BRAKE DRUM
Fig. 12 ADJUSTING GAUGE ON BRAKE SHOES
1 - BRAKE GAUGE
2 - BRAKE SHOES
Fig. 13 Brake Adjustment
1 - STAR WHEEL
2 - LEVER
3 - BRAKE SHOE WEB
4 - SCREWDRIVER
5 - ADJUSTING TOOL
6 - ADJUSTER SPRING
KJBRAKES - BASE 5 - 13
BRAKE PADS / SHOES (Continued)

OPERATION
When the brakes are applied fluid pressure is
exerted against the caliper piston. The fluid pressure
is exerted equally and in all directions. This means
pressure exerted against the caliper piston and
within the caliper bore will be equal (Fig. 14).
Fluid pressure applied to the piston is transmitted
directly to the inboard brake shoe. This forces the
shoe lining against the inner surface of the disc
brake rotor. At the same time, fluid pressure within
the piston bore forces the caliper to slide inward on
the mounting bolts. This action brings the outboard
brake shoe lining into contact with the outer surface
of the disc brake rotor.
In summary, fluid pressure acting simultaneously
on both piston and caliper, produces a strong clamp-
ing action. When sufficient force is applied, friction
will attempt to stop the rotors from turning and
bring the vehicle to a stop.
Application and release of the brake pedal gener-
ates only a very slight movement of the caliper and
piston. Upon release of the pedal, the caliper and pis-
ton return to a rest position. The brake shoes do not
retract an appreciable distance from the rotor. In
fact, clearance is usually at, or close to zero. The rea-
sons for this are to keep road debris from gettingbetween the rotor and lining and in wiping the rotor
surface clear each revolution.
The caliper piston seal controls the amount of pis-
ton extension needed to compensate for normal lining
wear.
During brake application, the seal is deflected out-
ward by fluid pressure and piston movement (Fig.
15). When the brakes (and fluid pressure) are
released, the seal relaxes and retracts the piston.
The amount of piston retraction is determined by
the amount of seal deflection. Generally the amount
is just enough to maintain contact between the pis-
ton and inboard brake shoe.
REMOVAL
(1) Install prop rod on the brake pedal to keep
pressure on the brake system.
(2) Raise and support vehicle.
(3) Remove front wheel and tire assembly.
(4) Drain small amount of fluid from master cylin-
der brake reservoir with suction gun.
(5) Remove the brake hose banjo bolt if replacing
caliper (Fig. 16).
(6) Remove the caliper mounting slide pin bolts
(Fig. 16).
(7) Remove the caliper from vehicle.
DISASSEMBLY
(1) Remove brake shoes from caliper.
(2) Drain brake fluid out of caliper.
(3) Take a piece of wood and pad it with one-inch
thickness of shop towels. Place this piece in the out-
board shoe side of the caliper in front of the piston.
This will cushion and protect caliper piston during
removal (Fig. 17).
Fig. 14 Brake Caliper Operation
1 - CALIPER
2 - PISTON
3 - PISTON BORE
4 - SEAL
5 - INBOARD SHOE
6 - OUTBOARD SHOE
Fig. 15 Lining Wear Compensation By Piston Seal
1 - PISTON
2 - CYLINDER BORE
3 - PISTON SEAL BRAKE PRESSURE OFF
4 - CALIPER HOUSING
5 - DUST BOOT
6 - PISTON SEAL BRAKE PRESSURE ON
5 - 14 BRAKES - BASEKJ
DISC BRAKE CALIPERS (Continued)

(4) Install the brake hose to the caliper withnew
seal washersand tighten fitting bolt to 31 N´m (23
ft. lbs.).
CAUTION: Verify brake hose is not twisted or
kinked before tightening fitting bolt.
(5) Remove the prop rod from the vehicle.
(6) Bleed the base brake system,(Refer to 5 -
BRAKES - STANDARD PROCEDURE) OR (Refer to
5 - BRAKES - STANDARD PROCEDURE).
(7) Install the wheel and tire assemblies (Refer to
22 - TIRES/WHEELS/WHEELS - STANDARD PRO-
CEDURE).
(8) Remove the supports and lower the vehicle.
(9) Verify a firm pedal before moving the vehicle.
DISC BRAKE CALIPER
ADAPTER
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the front wheel and tire assembly.
(3) Drain a small amount of fluid from master cyl-
inder brake reservoir with acleansuction gun.
(4) Bottom the caliper pistons into the caliper by
prying the caliper over.
(5) Remove the caliper mounting bolts (Fig. 16).
(6) Remove the disc brake caliper from the mount.
CAUTION: Never allow the disc brake caliper to
hang from the brake hose. Damage to the brake
hose will result. Provide a suitable support to hang
the caliper securely.
(7) Remove the inboard and outboard brake pads.
(Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL/
BRAKE PADS/SHOES - REMOVAL).
(8) Remove the caliper adapter mounting bolts
(Fig. 16).
INSTALLATION
(1) Install the caliper adapter mounting bolts.
Tighten the mounting bolts to 135 N´m (100 ft.lbs).
(2) Install the inboard and outboard pads. (Refer
to 5 - BRAKES/HYDRAULIC/MECHANICAL/
BRAKE PADS/SHOES - INSTALLATION).
(3) Install the caliper mounting bolts.
(4) Install the tire and wheel assembly. (Refer to
22 - TIRES/WHEELS/WHEELS - STANDARD PRO-
CEDURE).
ROTORS
DIAGNOSIS AND TESTING - DISC BRAKE
ROTOR
The rotor braking surfaces should not be refinished
unless necessary.
Light surface rust and scale can be removed with a
lathe equipped with dual sanding discs. The rotor
surfaces can be restored by machining in a disc brake
lathe if surface scoring and wear are light.
Replace the rotor under the following conditions:
²severely scored
²tapered
²hard spots
²cracked
²below minimum thickness
ROTOR MINIMUM THICKNESS
Measure rotor thickness at the center of the brake
shoe contact surface. Replace the rotor if worn below
minimum thickness, or if machining would reduce
thickness below the allowable minimum.
Rotor minimum thickness is usually specified on
the rotor hub. The specification is either stamped or
cast into the hub surface.
ROTOR RUNOUT
Check rotor lateral runout with dial indicator
C-3339 (Fig. 28). Excessive lateral runout will cause
brake pedal pulsation and rapid, uneven wear of the
brake shoes. Position the dial indicator plunger
approximately 25.4 mm (1 in.) inward from the rotor
edge. The dial indicator should be positioned in the
center of the rotor surface. Maximum allowable rotor
runout is 0.102 mm (0.004 in.).
ROTOR THICKNESS VARIATION
Variations in rotor thickness will cause pedal pul-
sation, noise and shudder.
Measure rotor thickness at 6 to 12 points around
the rotor face (Fig. 29).
Position the micrometer approximately 25.4 mm (1
in.) from the rotor outer circumference for each mea-
surement.
Thickness should notvaryby more than 0.013 mm
(0.0005 in.) from point-to-point on the rotor. Machine
or replace the rotor if necessary.
5 - 18 BRAKES - BASEKJ
DISC BRAKE CALIPERS (Continued)

STANDARD PROCEDURE - DISC BRAKE
ROTOR
The disc brake rotor can be machined if scored or
worn. The lathe must machine both sides of the rotor
simultaneously with dual cutter heads. The rotor
mounting surface must be clean before placing on the
lathe. Equipment capable of machining only one side
at a time may produce a tapered rotor. A hub
mounted on-vehicle lathe is recommended. This type
of lathe trues the rotor to the vehicles hub/bearing.CAUTION: Brake rotors that do not meet minimum
thickness specifications before or after machining
must be replaced.
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the tire and wheel assembly.
(3) Remove the caliper adapter (Fig. 30). (Refer to
5 - BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPER ADAPTER - REMOVAL).
CAUTION: Never allow the disc brake caliper to
hang from the brake hose. Damage to the brake
hose will result. Provide a suitable support to hang
the caliper securely.
(4) Remove the disc brake rotor.
INSTALLATION
(1) Install the disc brake rotor to the hub.
(2) Install the caliper mounting adapter. (Refer to
5 - BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPER ADAPTER - INSTALLATION).
(3) Install the tire and wheel assembly. (Refer to
22 - TIRES/WHEELS/WHEELS - STANDARD PRO-
CEDURE).
Fig. 28 Checking Rotor Runout And Thickness
Variation
1 - DIAL INDICATOR
Fig. 29 Measuring Rotor Thickness
1 - MICROMETER
2 - ROTOR
Fig. 30 DISC BRAKE ROTOR
1 - DISC BRAKE ROTOR
2 - CALIPER ADAPTER
3 - DISC BRAKE CALIPER
4 - SHOES
KJBRAKES - BASE 5 - 19
ROTORS (Continued)

FLUID RESERVOIR
REMOVAL
(1) Install prop rod on brake pedal to keep pres-
sure on the brake system.
(2) Remove reservoir cap and siphon fluid into
drain container.
(3) Remove the electrical connector from the fluid
level switch in the reservoir.
(4) Remove the reservoir mounting bolt.
(5) Remove the reservoir from the master cylinder
by pulling upwards.
(6) Remove old grommets from cylinder body.
INSTALLATION
(1) Fill and bleed master cylinder on bench before
installation in vehicle.
CAUTION: Do not use any type of tool to install the
grommets. Tools may cut, or tear the grommets cre-
ating a leak problem after installation. Install the
grommets using finger pressure only.
(2) Lubricate new grommets with clean brake fluid
and Install new grommets in cylinder body. Use fin-
ger pressure to install and seat grommets.
(3) Start reservoir in grommets. Then rock reser-
voir back and forth while pressing downward to seat
it in grommets.
(4) Install the mounting bolt for the reservoir to
the master cylinder.
(5) Reconnect the electrical connector to the fluid
reservoir level switch.(6) Remove the prop rod from the vehicle.
(7) Fill and bleed base brake system,(Refer to 5 -
BRAKES - STANDARD PROCEDURE).
FLUID
DIAGNOSIS AND TESTING - BRAKE FLUID
CONTAMINATION
Indications of fluid contamination are swollen or
deteriorated rubber parts.
Swollen rubber parts indicate the presence of
petroleum in the brake fluid.
To test for contamination, put a small amount of
drained brake fluid in clear glass jar. If fluid sepa-
rates into layers, there is mineral oil or other fluid
contamination of the brake fluid.
If brake fluid is contaminated, drain and thor-
oughly flush system. Replace master cylinder, propor-
tioning valve, caliper seals, wheel cylinder seals,
Antilock Brakes hydraulic unit and all hydraulic
fluid hoses.
STANDARD PROCEDURES - MASTER
CYLINDER FLUID LEVEL
Always clean the master cylinder reservoir and cap
before adding fluid. This will prevent dirt from fall-
ing in the reservoir and contaminating the brake
fluid.
The reservoir has a ADD and a FULL mark on the
side (Fig. 42) fill to the FULL mark.
Fig. 41 MASTER CYLINDER
1 - FLUID RESERVOIR
2 - BOOSTER
3 - FLUID LEVEL SWITCH
4 - MASTER CYLINDER
5 - FLUID LEVEL MARKS
Fig. 42 TYPICAL - MASTER CYLINDER FLUID
LEVEL
1 - FLUID LEVEL MARKS
2 - RESERVOIR
5 - 26 BRAKES - BASEKJ
MASTER CYLINDER (Continued)

SPECIFICATIONS
BRAKE FLUID
The brake fluid used in this vehicle must conform
to DOT 3 specifications and SAE J1703 standards.
No other type of brake fluid is recommended or
approved for usage in the vehicle brake system. Use
only Mopar brake fluid or an equivalent from a
tightly sealed container.
CAUTION: Never use reclaimed brake fluid or fluid
from an container which has been left open. An
open container will absorb moisture from the air
and contaminate the fluid.
CAUTION: Never use any type of a petroleum-based
fluid in the brake hydraulic system. Use of such
type fluids will result in seal damage of the vehicle
brake hydraulic system causing a failure of the
vehicle brake system. Petroleum based fluids would
be items such as engine oil, transmission fluid,
power steering fluid, etc.
DRUM
DIAGNOSIS AND TESTING - BRAKE DRUM
The maximum allowable diameter of the drum
braking surface is indicated on the drum outer edge.
Generally, a drum can be machined to a maximum of
1.52 mm (0.060 in.) oversize. Always replace the
drum if machining would cause drum diameter to
exceed the size limit indicated on the drum.
BRAKE DRUM RUNOUT
Measure drum diameter and runout with an accu-
rate gauge. The most accurate method of measure-
ment involves mounting the drum in a brake lathe
and checking variation and runout with a dial indi-
cator.
Variations in drum diameter should not exceed
0.076 mm (0.003 in.). Drum runout should not exceed
0.20 mm (0.008 in.) out of round. Machine the drum
if runout or variation exceed these values. Replace
the drum if machining causes the drum to exceed the
maximum allowable diameter.
STANDARD PROCEDURES - BRAKE DRUM
MACHINING
The brake drums can be machined on a drum lathe
when necessary. Initial machining cuts should be lim-
ited to 0.12 - 0.20 mm (0.005 - 0.008 in.) at a time as
heavier feed rates can produce taper and surface
variation. Final finish cuts of 0.025 to 0.038 mm(0.001 to 0.0015 in.) are recommended and will gen-
erally provide the best surface finish.
Be sure the drum is securely mounted in the lathe
before machining operations. A damper strap should
always be used around the drum to reduce vibration
and avoid chatter marks.
The maximum allowable diameter of the drum
braking surface is stamped or cast into the drum
outer edge.
CAUTION: Replace the drum if machining will cause
the drum to exceed the maximum allowable diame-
ter.
SUPPORT PLATE
REMOVAL
REMOVAL - 198 RBI AXLE
(1) Remove wheel and tire assembly.
(2) Remove the brake drum.
(3) Remove the brake shoes.
(4) Remove parking brake cable from parking
brake lever.
(5) Compress parking brake cable retainer tabs.
Then push retainer and cable through and out of
support plate.
(6) Disconnect brake line at wheel cylinder.
(7) Remove wheel cylinder from support plate,(Re-
fer to 5 - BRAKES/HYDRAULIC/MECHANICAL/
WHEEL CYLINDERS - REMOVAL).
(8) Remove the four bolts attaching the support
plate to axle and remove the support plate with the
axle, bearing and seal.
(9) Remove axle shaft,(Refer to 3 - DIFFEREN-
TIAL & DRIVELINE/REAR AXLE/AXLE SHAFTS -
REMOVAL).
REMOVAL - 8 1/4 AXLE
(1) Remove the wheel and tire assembly.
(2) Remove the brake drum.
(3) Install the brake pedal prop rod.
(4) Remove the brake shoes (Refer to 5 - BRAKES/
HYDRAULIC/MECHANICAL/BRAKE PADS/SHOES
- REMOVAL).
(5) Remove parking brake cable from parking
brake lever.
(6) Compress parking brake cable retainer tabs.
Then push retainer and cable through and out of
support plate.
(7) Disconnect the brake line at wheel cylinder.
(8) Remove the wheel cylinder from the support
plate,(Refer to 5 - BRAKES/HYDRAULIC/MECHAN-
ICAL/WHEEL CYLINDERS - REMOVAL).
KJBRAKES - BASE 5 - 27
FLUID (Continued)

(9) Remove the axle shaft, (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/REAR AXLE - 8 1/4/AXLE
SHAFTS - REMOVAL).
(10) Remove the bolts attaching the support plate
to the axle and remove the support plate (Fig. 43).
INSTALLATION
INSTALLATION - 198 RBI AXLE
(1) Install the support plate on the axle flange.
Tighten 75 N´m (55 ft. lbs.)
(2) Install the axle, bearing and seal into the hous-
ing and tighten the four attaching bolts to 61 N´m
(45 ft. lbs.).
(3) Install the wheel cylinder,(Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/WHEEL
CYLINDERS - INSTALLATION).
(4) Install the brake line in the wheel cylinder.
(5) Install the parking brake cable in the support
plate.
(6) Connect parking brake cable to lever on sec-
ondary shoe and install brake shoes on support plate.
(7) Adjust the brake shoes to the drum with the
brake gauge.
(8) Install the brake drum and wheel and tire
assembly (Refer to 22 - TIRES/WHEELS/WHEELS -
STANDARD PROCEDURE).
(9) Bleed brake system,(Refer to 5 - BRAKES -
STANDARD PROCEDURE) OR (Refer to 5 -
BRAKES - STANDARD PROCEDURE).
INSTALLATION - 8 1/4 AXLE
(1) Install the support plate on the axle flange.
Tighten attaching bolts to 61 N´m (45 ft. lbs.) (Fig.
43).(2) Install the wheel cylinder,(Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/WHEEL
CYLINDERS - INSTALLATION).
(3) Install the brake line in the wheel cylinder and
tighten the line to 14 N´m (124 in.lbs.)..
(4) Remove the brake pedal prop rod.
(5) Install the parking brake cable in the support
plate.
(6) Install the axle shaft, (Refer to 3 - DIFFEREN-
TIAL & DRIVELINE/REAR AXLE - 8 1/4/AXLE
SHAFTS - INSTALLATION).
(7) Connect the parking brake cable to the lever on
the primary shoe and install the brake shoes on the
support plate (Refer to 5 - BRAKES/HYDRAULIC/
MECHANICAL/BRAKE PADS/SHOES - INSTALLA-
TION).
(8) Adjust the brake shoes to the drum with the
brake gauge (Refer to 5 - BRAKES/HYDRAULIC/
MECHANICAL/BRAKE PADS/SHOES - ADJUST-
MENTS).
(9) Install the brake drum.
(10) Install the wheel and tire assembly (Refer to
22 - TIRES/WHEELS/WHEELS - STANDARD PRO-
CEDURE).
(11) Bleed the brake system,(Refer to 5 - BRAKES
- STANDARD PROCEDURE).
WHEEL CYLINDERS
REMOVAL
(1) Remove wheel and tire assembly.
(2) Remove brake drum.
(3) Install brake pedal prop rod.
(4) Disconnect wheel cylinder brake line.
(5) Remove brake shoe return springs and move
shoes out of engagement with cylinder push rods.
(6) Remove cylinder attaching bolts and remove
cylinder from support plate (Fig. 44).
DISASSEMBLY
(1) Remove push rods and boots (Fig. 45).
(2) Press pistons, cups and spring and expander
out of cylinder bore.
(3) Remove bleed screw.
CLEANING
Clean the cylinder and pistons with clean brake
fluid or brake cleaner only. Do not use any other
cleaning agents.
Dry the cylinder and pistons with compressed air.
Do not use rags or shop towels to dry the cylinder
components. Lint from cloth material will adhere to
the cylinder bores and pistons.
Fig. 43 SUPPORT PLATE 8 1/4
1 - SUPPORT PLATE
2 - MOUNTING NUTS
5 - 28 BRAKES - BASEKJ
SUPPORT PLATE (Continued)

INSPECTION
Inspect the cylinder bore. Light discoloration and
dark stains in the bore are normal and will not
impair cylinder operation.
The cylinder bore can be lightly polished but only
with crocus cloth. Replace the cylinder if the bore is
scored, pitted or heavily corroded. Honing the bore to
restore the surface is not recommended.
Inspect the cylinder pistons. The piston surfaces
should be smooth and free of scratches, scoring and
corrosion. Replace the pistons if worn, scored, or cor-
roded. Do not attempt to restore the surface by sand-
ing or polishing.Discard the old piston cups and the spring and
expander. These parts are not reusable. The original
dust boots may be reused but only if they are in good
condition.
ASSEMBLY
(1) Lubricate wheel cylinder bore, pistons, piston
cups and spring and expander with clean brake fluid.
(2) Install first piston in cylinder bore. Then
install first cup in bore and against piston.Be sure
lip of piston cup is facing inward (toward
spring and expander) and flat side is against
piston.
(3) Install spring and expander followed by
remaining piston cup and piston.
(4) Install boots on each end of cylinder and insert
push rods in boots.
(5) Install cylinder bleed screw.
INSTALLATION
(1) Install cylinder mounting bolts and tighten to
20 N´m (15 ft. lbs.) (Fig. 44).
(2) Connect brake line to cylinder and tighten to
14 N´m (124 in. lbs.).
(3) Install the brake shoe return springs.
(4) Remove the brake pedal prop rod.
(5) Install the brake drum.
(6) Install the wheel and tire assembly (Refer to 22
- TIRES/WHEELS/WHEELS - STANDARD PROCE-
DURE).
(7) Bleed base brake system (Refer to 5 - BRAKES
- STANDARD PROCEDURE).
PARKING BRAKE
DESCRIPTION
The parking brake is a hand lever and cable oper-
ated system used to apply the rear brakes.
OPERATION
A hand operated lever in the passenger compart-
ment is the main application device. The front cable
is connected between the hand lever and the rear
cables with an equalizer.
The rear cables are connected to the actuating
lever on each primary brake shoe. The levers are
attached to the brake shoes by a pin either pressed
into, or welded to the lever. A clip is used to secure
the pin in the brake shoe. The pin allows each lever
to pivot independently of the brake shoe.
To apply the parking brakes, the hand lever is
pulled upward. This pulls the rear brake shoe actu-
ating levers forward, by means tensioner and cables.
As the actuating lever is pulled forward, the parking
brake strut (which is connected to both shoes), exerts
Fig. 44 WHEEL CYLINDER
1 - WHEEL CYLINDER
2 - SUPPORT PLATE
Fig. 45 Wheel Cylinder Components±Typical
1 - SPRING
2 - CYLINDER
3 - PISTON CLIP
4 - BOOT
5 - PUSH ROD
6 - PISTON
7 - BLEED SCREW
8 - CUP EXPANDERS
KJBRAKES - BASE 5 - 29
WHEEL CYLINDERS (Continued)

BRAKES - ABS
TABLE OF CONTENTS
page page
BRAKES - ABS
DESCRIPTION.........................32
OPERATION...........................32
DIAGNOSIS AND TESTING - ANTILOCK
BRAKING SYSTEM....................33
STANDARD PROCEDURE - ABS BRAKE
BLEEDING...........................33
SPECIFICATIONS.......................33
ELECTRICAL
DESCRIPTION.........................34
OPERATION...........................34FRONT WHEEL SPEED SENSOR
REMOVAL.............................34
INSTALLATION.........................34
REAR WHEEL SPEED SENSOR
REMOVAL.............................35
INSTALLATION.........................35
HCU (HYDRAULIC CONTROL UNIT)
DESCRIPTION.........................35
OPERATION...........................35
REMOVAL.............................36
INSTALLATION.........................36
BRAKES - ABS
DESCRIPTION
ANTILOCK BRAKING SYSTEM
The purpose of the antilock system is to prevent
wheel lockup during periods of high wheel slip. Pre-
venting lockup helps maintain vehicle braking action
and steering control.
The antilock CAB activates the system whenever
sensor signals indicate periods of high wheel slip.
High wheel slip can be described as the point where
wheel rotation begins approaching 20 to 30 percent of
actual vehicle speed during braking. Periods of high
wheel slip occur when brake stops involve high pedal
pressure and rate of vehicle deceleration.
Battery voltage is supplied to the CAB ignition ter-
minal when the ignition switch is turned to Run posi-
tion. The CAB performs a system initialization
procedure at this point. Initialization consists of a
static and dynamic self check of system electrical
components.
The static check occurs after the ignition switch is
turned to Run position. The dynamic check occurs
when vehicle road speed reaches approximately 30
kph (18 mph). During the dynamic check, the CAB
briefly cycles the pump and solenoids to verify oper-
ation.
If an ABS component exhibits a fault during ini-
tialization, the CAB illuminates the amber warning
light and registers a fault code in the microprocessor
memory.
ELECTRONIC BRAKE DISTRIBUTION
The electronic brake distribution (EBD) functions
like a rear proportioning valve. The EBD system usesthe ABS system to control the slip of the rear wheels
in partial braking range. The braking force of the
rear wheels is controlled electronically by using the
inlet and outlet valves located in the HCU.
OPERATION
ANTILOCK BRAKING SYSTEM
During normal braking, the master cylinder, power
booster and wheel brake units all function as they
would in a vehicle without ABS. The HCU compo-
nents are not activated.
During antilock braking fluid pressure is modu-
lated according to wheel speed, degree of slip and
rate of deceleration. A sensor at each wheel converts
wheel speed into electrical signals. These signals are
transmitted to the CAB for processing and determi-
nation of wheel slip and deceleration rate.
The ABS system has three fluid pressure control
channels. The front brakes are controlled separately
and the rear brakes in tandem. A speed sensor input
signal indicating a high slip condition activates the
CAB antilock program. Two solenoid valves are used
in each antilock control channel. The valves are all
located within the HCU valve body and work in pairs
to either increase, hold, or decrease apply pressure as
needed in the individual control channels. The sole-
noid valves are not static during antilock braking.
They are cycled continuously to modulate pressure.
Solenoid cycle time in antilock mode can be mea-
sured in milliseconds.
ELECTRONIC BRAKE DISTRIBUTION
Upon entry into EBD the inlet valve for the rear
brake circuit is switched on so that the fluid supply
from the master cylinder is shut off. In order to
decrease the rear brake pressure the outlet valve for
5 - 32 BRAKES - ABSKJ