REAR DRUM BRAKE SHOE ADJUSTMENT
NOTE: Normally, self adjusting drum brakes will
not require manual brake shoe adjustment.
Although in the event of a brake reline it is advis-
able to make the initial adjustment manually to
speed up the adjusting time.
(1) Raise the vehicle so that the rear wheels are
free to turn. See Hoisting Recommendations in the
Lubrication And Maintenance Section, at the front of
this service manual.
Remove the park brake cable, for the wheel of the
vehicle that is being worked on, from the park brake
cable equalizer (Fig. 196). This is required to gain
access to the star wheel. If the cable is not removed
from the equalizer, the cable and spring inside of the
brake drum is in the way of the star wheel.
(2) Remove rubber plug, from rear brake adjusting
hole, in the rear brake support plate (Fig. 197).(3)Be sure parking brake lever is fully
released.
(4) Insert Brake Adjusting, Special Tool C-3784 or
equivalent through the adjusting hole in support
plate and against star wheel of adjusting screw. Move
handle of tool upward until a slight drag is felt when
road wheel is rotated.
(5) Insert a thin screwdriver or piece of welding
rod into brake adjusting hole. Push adjusting lever
out of engagement with star wheel.Care should be
taken so as not to bend adjusting lever or dis-
tort lever spring.While holding adjusting lever out
of engagement, back off star wheel to ensure a free
wheel with no brake shoe drag.
(6) Repeat above adjustment at the other rear
wheel.
(7) Install adjusting hole rubber plug (Fig. 197) in
rear brake support plates.
(8) Install park brake cables on park brake cable
equalizer (Fig. 196).
PARK BRAKE SHOES (WITH REAR DISC BRAKES)
CAUTION: Before adjusting the park brake shoes
be sure that the park brake pedal is in the fully
released position. If park brake pedal is not in the
fully released position, the park brake shoes can
not be accurately adjusted.
(1) Raise vehicle.
(2) Remove tire and wheel.
(3) Remove disc brake caliper from caliper adapter
(Fig. 198). If required, refer to Rear Disc Brake Cal-
iper in the Removal And Installation Section in this
group of the service manual for the removal proce-
dure.
Fig. 196 Park Brake Cable Equlizer
Fig. 197 Brake Adjusting Hole Plug
Fig. 198 Disc Brake Caliper
NSBRAKES 5 - 79
ADJUSTMENTS (Continued)
group of the service manual for the installation pro-
cedure.
(13) Install wheel and tire.
(14) Tighten the wheel mounting nuts in the
proper sequence until all nuts are torqued to half the
specified torque. Then repeat the tightening sequence
to the full specified torque of 129 N´m (95 ft. lbs.).
(15) Lower vehicle.
(16) Apply and release the park brake pedal one
time. This will seat and correctly adjust the park
brake cables.
CAUTION: Before moving vehicle, pump brake
pedal several times to ensure the vehicle has a firm
enough pedal to stop the vehicle.
(17) Road test the vehicle to ensure proper func-
tion of the vehicle's brake system.
PARK BRAKE CABLE ADJUSTMENT
The park brake cables on this vehicle have an
automatic self adjuster built into the park brake
pedal mechanism. When the foot operated park brake
pedal is in its released (upward most) position, a
clock spring automatically adjusts the park brake
cables. The park brake cables are adjusted (ten-
sioned) just enough to remove all the slack from the
cables. The automatic adjuster system will not over
adjust the cables causing rear brake drag.
Due to the automatic adjust feature of the park
brake pedal, adjustment of the parking brake cables
on these vehicles relies on proper drum brake and
park brake shoe adjustment. See Rear Brake Adjust-
ment and Park Brake Shoe Adjustment in the Ser-
vice Adjustments Section in this group of the service
manual.
When the park brake pedal is applied the self
adjuster is by-passed and the pedal operates nor-
mally to engage the park brakes.
When a service procedure needs to be performed on
the park brake pedal or the park brake cables, the
automatic self adjuster can be manually locked out
by the service technician.
PROPORTIONING VALVE (HEIGHT SENSING)
Proportioning valve actuator adjustment will be
required if there is a complaint of premature rear
wheel lockup and the front and rear brake shoe lin-
ings checked OK during inspection, the height sens-
ing proportioning valve required replacement, or
there is a complaint of excessive pedal effort and the
vacuum booster and brake pedal checked OK. Make
sure the proportioning valve and the mounting
bracket are firmly attached to the vehicle. Then, pro-
ceed with the following procedure to perform the
adjustment of the actuator.(1) Raise vehicle. Vehicle is to be raised and sup-
ported on jackstands or with a frame contact type
hoist so the rear suspension of the vehicle is hanging
free. See hoisting in the Lubrication And Mainte-
nance section of this service manual.
(2) Remove rear wheels/tires.
(3) Using an appropriate jack, support the rear
axle prior to the removal of the track bar and shock
absorber bolts from the rear axle.
(4) Unbolt the track bar from the rear axle.
(5) Unbolt both shock absorbers from the rear
axle.
(6) Loosen (do not remove) both of the leaf spring
to front spring hanger pivot bolts.
NOTE: When lowering the rear axle be sure that the
leaf springs do not come in contact with the hoist
limiting the downward movement of the axle. If this
occurs an improper adjustment of the actuator may
result.
(7) Lower the rear axle so it is at its farthest point
of downward movement.
(8) Loosen the adjustment nut (Fig. 203) on the
actuator.
(9) Be sure the hooked end of the actuator is cor-
rectly (fully) seated in the clip on the proportioning
valve lever and that the clip is correctly positioned
on the lever of the proportioning valve.
(10) Pull the housing of the proportioning valve
actuator toward the spring hanger (Fig. 203) until
the lever on the proportioning valve bottoms on the
body of the proportioning valve.Hold the propor-
tioning valve actuator in this position while
tightening the adjustment nut (Fig. 203) to a
torque of 5 N´m (45 in. lbs.). Proportioning
valve adjustment is now complete.
(11) Install shock absorbers and track bar on rear
axle.Do not tighten the mounting bolts for any
of the loosened suspension components at this
time.
(12) Install the wheel/tires.
Fig. 203 Proportioning Valve Actuator Adjustment
NSBRAKES 5 - 81
ADJUSTMENTS (Continued)
BRAKE ACTUATION SYSTEM
ACTUATION:
Vacuum Operated Power Brakes.........Standard
Hydraulic System...........Dual-Diagonally Split
Antilock Brake Sytem (Teves Mark-20)...........
MASTER CYLINDER ASSEMBLY:
Supplier..............................Bosch
Type For Non-ABSAnd
ABS Brakes. . . .Conventional Compensating Port
Type For ABS Brakes
With Traction Control . . .Dual Center Port Design
Body Material...............Anodized Aluminum
Reservoir Material................Polypropelene
MASTER CYLINDER BORE /
STROKE AND SPLIT:
ABS W/Disc/Drum Brakes......23.8 mm x 36 mm
(.937 in. x 1.47 in.)
AWD W/Disc/Disc Brakes........25.4 mm x 39 mm
(1.00 in. x 1.50 in.)
Displacement Split.....................50/50
MASTER CYLINDER FLUID OUTLET PORTS:
Non-ABS And ABS . . .Primary 7/16±24 Secondary 7/
16±24
ABS With Traction Control.......Primary M12 x 1
Secondary M12 x 1
Outlet Fitting Type Non-ABS
AndABS...........Double Wall Inverted Flare
Outlet Fitting Type ABS With
Traction Control...................ISO Flare
ABS HYDRAULIC CONTROL UNIT:
Hydraulic Tube Fitting Type............ISO Flare
BOOSTER:
Make/Type.................Bosch Vacuum Assist
Mounting Studs.....................M8x1.25
Type .........................270 ZLT RSMV
Boost At 20 inches Of
Manifold Vacuum...........3800 N´m (850 lbs.)
PROPORTIONING VALVE:
Material...........................Aluminum
Function....................Hydraulic Pressure
Proportioning To Rear Brakes
BRAKE PEDAL
Pedal Ratio.............................3.36
BRAKE FASTENER TORQUE SPECIFICATIONS
DESCRIPTION TORQUE
BRAKE TUBES:
Tube Nuts To Fittings And
Components..............17N´m(145 in. lbs.)
BRAKE HOSE:
To Caliper Banjo Bolt..........48N´m(35ft.lbs.)
Intermediate Bracket.........12N´m(105 in. lbs.)
MASTER CYLINDER:
To Vacuum Booster
Mounting Nut............25N´m(225 in. lbs.)
FIXED PROPORTIONING VALVE:
To Frame Rail Attaching
Bolts....................14N´m(125 in. lbs.)
HEIGHT SENSING PROPORTIONING VALVE:
To Mounting Bracket
Attaching Bolts...........23N´m(200 in. lbs.)
Actuator Assembly
Adjustment Nut.............5N´m(45in.lbs.)
Mounting Bracket To Frame
Rail Bolts................17N´m(150 in. lbs.)
JUNCTION BLOCK (NON-ABS BRAKES)
To Suspension Cradle
Mounting Bolt............28N´m(250 in. lbs.)
VACUUM BOOSTER:
To Dash Panel Mounting
Nuts....................28N´m(250 in. lbs.)
REAR WHEEL CYLINDER:
To Support Plate Mounting
Bolts.....................8N´m(75in.lbs.)
Bleeder Screw...............10N´m(80in.lbs.)
BRAKE SUPPORT PLATE:
To Rear Axle Mounting Bolts . . .130 N´m (95 ft. lbs.)
DISC BRAKE CALIPER:
Guide Pin Bolts..............41N´m(30ft.lbs.)
Bleeder Screw..............15N´m(125 in. lbs.)
ABS HYDRAULIC CONTROL UNIT:
Mounting Bracket To
Suspension Cradle Bolts.....28N´m(250 in. lbs.)
To Mounting Bracket Isolator
Attaching Bolts............11N´m(97in.lbs.)
CAB To HCU Mounting Screws . . .2 N´m (17 in. lbs.)
WHEEL SPEED SENSOR:
To Axle Or Steering Knuckle
Mounting Bolt............12N´m(105 in. lbs.)
PARKING BRAKE:
Pedal Assembly Mounting
Bolts....................28N´m(250 in. lbs.)
REAR HUB AND BEARING:
To Axle Mounting Bolts........129 N´m (95 ft. lbs.)
WHEEL:
Stud Lug Nut........115±156 N´m (84-115 ft. lbs.)
NSBRAKES 5 - 83
SPECIFICATIONS (Continued)
TEVES MARK 20 ABS WITH TRACTION
CONTROL± TRACTION CONTROL HYDRAULIC
CIRCUIT ± SOLENOID AND SHUTTLE VALVE
FUNCTION
This hydraulic circuit diagram (Fig. 16) shows a
vehicle equipped with ABS and traction control in
the traction control mode. The hydraulic circuit (Fig.
16) shows a situation where a driven wheel is spin-
ning and brake pressure is required to reduce its
speed. The normally open ASR valve (Fig. 16) is ener-
gized to isolate the brake fluid being pumped from
the master cylinder and to isolate the driven wheel.
Also, the normally open ASR valve bypasses the
pump output back to the master cylinder at a fixed
pressure setting. The normally open and normally
closed valves (Fig. 16) modulate the brake pressure
as required to the spinning wheel.
DIAGNOSIS AND TESTING
ABS GENERAL DIAGNOSTICS INFORMATION
This section contains the information necessary to
diagnose the ITT Teves Mark 20 ABS Brake System.
Specifically, this section should be used to help diag-
nose conditions which result in any of the following:
(1) ABS Warning Lamp turned on.(2) Brakes Lock-up on hard application
Diagnosis of base brake conditions which are obvi-
ously mechanical in nature should be directed to
Group 5 Brakes in this service manual. This includes
brake noise, brake pulsation, lack of power assist,
parking brake, Red BRAKE Warning Lamp lighting,
or vehicle vibration during normal braking.
Many conditions that generate customer com-
plaints may be normal operating conditions, but are
judged to be a problem due to not being familiar with
the ABS system. These conditions can be recognized
without performing extensive diagnostic work, given
adequate understanding of the operating principles
and performance characteristics of the ABS. See the
ABS System Operation Section in this group of the
service manual to familiarize yourself with the oper-
ating principles of the ABS system.
ABS WIRING DIAGRAM INFORMATION
During the diagnosis of the antilock brake system
it may become necessary to reference the wiring dia-
grams covering the antilock brake system and its
components. For wiring diagrams refer to Antilock
Brakes in Group 8W of this service manual. This
group will provide you with the wiring diagrams and
the circuit description and operation information cov-
ering the antilock brake system.
Fig. 15 ABS With Traction Control ABS Braking Hydraulic Circuit
NSBRAKES 5 - 95
DESCRIPTION AND OPERATION (Continued)
SPECIFICATIONS
SPEED SENSOR TONE WHEEL RUNOUT
The total indicator runout allowed for both the
front and rear tone wheel measured using a dial indi-
cator is 0.15 mm (.006 in.).
WHEEL SPEED SENSOR TO TONE WHEEL
CLEARANCE
FRONT WHEEL
Minimum Clearance .35mm (.014 in.)
Maxamum Clearance 1.2 mm (.047 in.)
REAR WHEEL
Minimum Clearance .40mm (.016 in.)
Maxamum Clearance 1.2 mm (.047 in.)
BRAKE FASTENER TORQUE SPECIFICATIONS
DESCRIPTION TORQUE
BRAKE TUBES:
Tube Nuts To Fittings And
Components..............17N´m(145 in. lbs.)
BRAKE HOSE:
To Caliper Banjo Bolt..........48N´m(35ft.lbs.)
Intermediate Bracket.........12N´m(105 in. lbs.)
MASTER CYLINDER:
To Vacuum Booster
Mounting Nut............25N´m(225 in. lbs.)
FIXED PROPORTIONING VALVE:
To Frame Rail Attaching
Bolts....................14N´m(125 in. lbs.)
HEIGHT SENSING PROPORTIONING VALVE:
To Mounting Bracket
Attaching Bolts...........23N´m(200 in. lbs.)
Actuator Assembly
Adjustment Nut.............5N´m(45in.lbs.)
Mounting Bracket To
Frame Rail Bolts..........17N´m(150 in. lbs.)
JUNCTION BLOCK (NON-ABS BRAKES)
To Suspension Cradle
Mounting Bolt............28N´m(250 in. lbs.)
VACUUM BOOSTER:
To Dash Panel Mounting
Nuts....................28N´m(250 in. lbs.)DESCRIPTION TORQUE
REAR WHEEL CYLINDER:
To Support Plate Mounting
Bolts.....................8N´m(75in.lbs.)
Bleeder Screw...............10N´m(80in.lbs.)
BRAKE SUPPORT PLATE:
To Rear Axle Mounting Bolts . . .130 N´m (95 ft. lbs.)
DISC BRAKE CALIPER:
Guide Pin Bolts..............41N´m(30ft.lbs.)
Bleeder Screw..............15N´m(125 in. lbs.)
ABS HYDRAULIC CONTROL UNIT:
Mounting Bracket To
Suspension Cradle Bolts.....28N´m(250 in. lbs.)
To Mounting Bracket Isolator
Attaching Bolts............11N´m(97in.lbs.)
CAB To HCU Mounting Screws . . .2 N´m (17 in. lbs.)
WHEEL SPEED SENSOR:
To Axle Or Steering Knuckle
Mounting Bolt............12N´m(105 in. lbs.)
PARKING BRAKE:
Pedal Assembly Mounting
Bolts....................28N´m(250 in. lbs.)
REAR HUB AND BEARING:
To Axle Mounting Bolts........129 N´m (95 ft. lbs.)
WHEEL:
Stud Lug Nut........115±156 N´m (84-115 ft. lbs.)
5 - 112 BRAKESNS
BRAKES
CONTENTS
page page
GENERAL INFORMATION
BASE BRAKE SYSTEM COMPONENT
DESCRIPTION........................ 1
DESCRIPTION AND OPERATION
MASTER CYLINDER..................... 1
DIAGNOSIS AND TESTING
MASTER CYLINDER FLUID LEVEL CHECK . . . 2REAR DRUM BRAKE ADJUSTMENT........ 1
REMOVAL AND INSTALLATION
BRAKE PEDAL TORQUE SHAFT ASSEMBLY . . 4
FRONT PARK BRAKE CABLE AND LEVER
ASSEMBLY-RHD&LHD VEHICLES........ 2
GENERAL INFORMATION
BASE BRAKE SYSTEM COMPONENT DESCRIPTION
The standard brake system on this vehicle contains
the same components as brake systems described in
group 5 of the service manual, with the exception of
the brake pedal system and master cylinder. These
differences are mainly related to service procedures.
The major differences are as follows:
²Use of a torque shaft assembly to transfer brake
pedal travel to the power brake booster and master
cylinder on the left side of the vehicle
²A unique power brake booster and master cylin-
der.
Refer to the Base Brake System Component
Description in the General Information section of
group 5 for more information on components used in
the base brake system.
DESCRIPTION AND OPERATION
MASTER CYLINDER
The master cylinder used on this vehicle functions
the same as master cylinders used in other brake
systems. Refer to the Master Cylinder in the Descrip-
tion and Operation section of group 5 for more infor-
mation.
DIAGNOSIS AND TESTING
REAR DRUM BRAKE ADJUSTMENT
The rear drum brakes on front wheel drive vehicles
automatically adjust, when required, during the nor-
mal operation of the vehicle every time the brakes
are applied. Use the following procedure to test the
operation of the automatic adjuster.
Place the vehicle on a hoist with a helper in the
driver's seat to apply the brakes. Remove the access
plug from the adjustment slot in each brake support
plate to provide visual access of brake adjuster star
wheel. Disconnect parking brake cable from one side
of the vehicle at the equalizer under the vehicle at
the left frame rail. Working on the side of the vehicle
that parking brake cable is connected to, hold the
adjuster lever off the star wheel with a suitable tool,
and loosen the star wheel approximately 30 notches
in relation to the adjuster lever. This is to eliminate
the possibility that the brake is already properly
adjusted. Reconnect the parking brake cable and
repeat the procedure for the other side of the vehicle.
Fig. 1 Master Cylinder Assembly
NS/GSBRAKES 5 - 1
Upon application of the brake pedal, the lever
should move down, turning the star wheel. A definite
rotation of the star wheel should be seen if the auto-
matic adjuster is working properly. If no rotation of
the star wheel is observed when the pedal is consec-
utively pressed and released, the respective drum
will have to be removed and the adjuster serviced.
MASTER CYLINDER FLUID LEVEL CHECK
The master cylinder used in this vehicle has the
same fluid level markings as the master cylinders
used in other brake systems on the side of the fluid
resevoir. Refer to the Master Cylinder Fluid Level
Check in the Diagnosis and Testing section of group
5 for more information
REMOVAL AND INSTALLATION
FRONT PARK BRAKE CABLE AND LEVER
ASSEMBLY-RHD&LHD VEHICLES
REMOVE
(1) Raise vehicle on jackstands or centered on a
hoist. See Hoisting in the Lubrication and Mainte-
nance group of this service manual.
(2) Remove the intermediate and left rear park
brake cable from the park brake cable equalizer (Fig.
2).
(3) Remove the front park cable housing retainer
from body outrigger bracket (Fig. 3). Cable is remov-
able by sliding a 14 mm box wrench over cable
retainer and compressing the three retaining fingers.
Alternate method is to use an aircraft type hose
clamp and screwdriver.(4) Remove the two (2) retaining nuts and (2)
retaining bolts from the bottom of the parking brake/
gearshift lever bracket.
(5) Lower vehicle.
(6) Carefully lift the base of the gearshift boot
from the gearshift console to access the screws (Fig.
4).
Fig. 2 Park Brake Cable Attachment To Equalizer
Fig. 3 Front Park Brake Cable Attachment To Body
Fig. 4 Console and Gearshift boot
5 - 2 BRAKESNS/GS
DIAGNOSIS AND TESTING (Continued)
(7) Remove the four (4) retaining screws (Fig. 5).
(8) Pull the parking brake lever to the ªupº posi-
tion and lift the console (Fig. 5).
(9) Tilt the base of the gearshift boot and carefully
push through the opening in the console while lifting.
(10) Remove the three (3) nuts at the base of the
parking brake assembly.
(11) Release the parking brake assembly and lift
assembly off of the parking brake/gearshift lever
bracket.
(12) Unhook the loop on the end of the parking
brake from the equalizer bar on the parking brake/
gearshift lever bracket.
(13) Compress the parking brake cable retainer by
sliding a 14 mm box wrench over the cable retainer
and compress the three (3) retaining fingers.
(14) Remove the three (3) screws from the parking
brake grommet on the floor pan of the passenger
compartment.
(15) Lift the parking brake /gearshift lever bracket
and slide the parking brake cable out.
(16) Pull the cable through the floor pan from
inside the vehicle.
INSTALL
(1) Pass park brake cable assembly through hole
in floor pan from the inside of the vehicle.
(2) Pass cable strand button through the hole in
the pedal assembly bracket.
(3) Install parking brake cable to the brake/gear-
shift lever bracket by lifting the bracket and sliding
the cable in.
(4) Install the three (3) screws to the parking
brake grommet on the floor pan of the passenger
compartment.
(5) Compress the parking brake cable retainer by
sliding a 14 mm box wrench over the cable retainer
and compress the three (3) retaining fingers.
(6) Hook the loop on the end of the parking brake
to the equalizer bar on the parking brake/gearshift
lever bracket.
(7) Attach the parking brake assembly and place
assembly on the parking brake/gearshift lever
bracket.
(8) Install the three (3) nuts at the base of the
parking brake assembly.
(9) Pull the parking brake lever to the ªupº posi-
tion.
(10) Place the console over the parking brake/gear-
shift lever and tilt the base of the gearshift boot and
carefully pull it through the opening in the console.
(11) Install the four (4) retaining screws (Fig. 5).
(12) Carefully press the three (3) clips at the base
of the gearshift boot into the slots on the gearshift
console.
(13) Raise the vehicle.
(14) install the two (2) retaining nuts and (2)
retaining bolts to the bottom of the parking brake/
gearshift lever bracket.
(15) Install the front park cable housing retainer
to the body outrigger bracket (Fig. 3). Cable is
installed by sliding a 14 mm box wrench over cable
retainer and compressing the three retaining fingers.
Alternate method is to use an aircraft type hose
clamp and screwdriver.
(16) Install the intermediate and left rear park
brake cable to the park brake cable equalizer (Fig. 2).
(17) Lower the vehicle.
Fig. 5 Console Retaining Screws
NS/GSBRAKES 5 - 3
REMOVAL AND INSTALLATION (Continued)