Page 897 of 3573
POWER ASSISTED BRAKE SYSTEM 5C – 19
Brake Pedal N·m (kg·m/lb·ft)
20(2.0/15)20(2.0/15)
Page 898 of 3573
5C – 20 POWER ASSISTED BRAKE SYSTEM
Front and Rear Brakes N·m (kg·m/lb·ft)
74(7.5/54) Front disc brake
Rear disc brake
35(3.6/26)
74(7.5/54)155(15.8/115)
35(3.6/26)
104(10.6/77)
44(4.5/32)
8(0.8/69 IbKin)
8(0.8/69 IbKin)
Page 899 of 3573
POWER ASSISTED BRAKE SYSTEM 5C – 21
SPECIAL TOOLS
ILLUSTRATION PART NO. PARTNAME
Primary piston holder
5-8840-2306-0
(including master cylinder attach-
(J-39242)
ment and master cylinder plug)
5-8840-0277-0
Radiator cap tester
(J-24460-01)
5-8840-2300-0
Push rod gauge
(J-39216)
5-8840-0279-0
Vacuum pump
(J-23738-A)
5-8840-2305-0
Push rod support
(J-39241)
Page 900 of 3573
5C – 22 POWER ASSISTED BRAKE SYSTEM
GENERAL DESCRIPTION
MASTER CYLINDER
The master cylinder contains two pistons that supply
the hydraulic pressure for a dual-circuit braking
system. The primary piston provides the fluid
pressure to the front brakes, while the secondary
piston provides the fluid pressure to the rear brakes.
If the pressure is lost from either system, the
remaining system will function to stop the vehicle.
CAUTION:
1) The master cylinder is not repairable. If found
defective, it must be replaced as complete
assembly.
2) If any hydraulic component is removed or
disconneted, it may be necessary to bleed all or
part of the brake system.
3) The torque values specified are for dry,
unlubricated fasteners.
4) Perform service operations on a clean bench free
from all mineral oil materials.
330RW013
Page 901 of 3573
POWER ASSISTED BRAKE SYSTEM 5C – 23
VACUUM BOOSTER
This booster is a tandem vacuum unit with a diaphragm effective diameter 205 mm + 230 mm (gasoline
engine model) / 180 mm + 205 mm (diesel engine model). In normal operating mode, with the service
brakes in the released position, the tandem vacuum booster operates with vacuum on both sides of its
diaphragms. When the brakes are applied, air at atmospheric pressure is admitted to one side of each
diaphragm to provide the power assist. When the service brake is released, the atmospheric air is shut
off from the one side of each diaphragm. The air is then drawn from the booster through the vacuum
check valve to the vacuum source.
CAUTION:
1) If any hydraulic component is removed or disconnected, it may be necessary to bleed all or part of
the brake system.
2) The torque values specified are for dry, unlubricated fasteners.
3) The vacuum booster is not repairable and must be replaced as complete assembly.
Page 902 of 3573

5C – 24 POWER ASSISTED BRAKE SYSTEM
DISC BRAKES
The disc brake assembly consists of a caliper, piston, rotor, pad assembly and support bracket. The
caliper assembly has a single bore and is mounted to the support bracket with 2 mounting bolts. The
support bracket allows the caliper to move laterally against the rotor. The caliper is a one-piece casting
with the inboard side containing the piston bore. A square cut rubber seal is located in a groove in the
piston bore which provides the hydraulic seal between the piston and the cylinder wall.
NOTE:
1) Replace all components included in repair kits used to service this caliper.
2) Lubricate rubber parts with clean brake fluid to ease assembly.
3) If any hydraulic component is removed or disconnected, it may be necessary to bleed all or part of
the brake system.
4) Replace pads in axle sets only.
5) The torque values specified are for dry, unlubricated fasteners.
6) Perform service operation a clean bench free from all mineral oil materials.
OPERATION
Hydraulic pressure, created by applying the brake pedal, is converted by the caliper to a stopping force.
This force acts equally against the piston and the bottom of the caliper bore to move the piston outward
and to move (slide) the caliper inward resulting in a clamping action on the rotor. This clamping action
forces the linings against the rotor, creating friction to stop the vehicle.
Front disc brakes
Rear disc brakes
Page 903 of 3573
POWER ASSISTED BRAKE SYSTEM 5C – 25
ON-VEHICLE SERVICE
BRAKE HOSE REPLACEMENT
1
24
2
3
12
4
5
3
Front/Rear Caliper Brake Hose
Removal Steps
1. Brake pipe
2. Clip
3. Bolt and gasket
4. HoseInstallation Steps
To install, follow the removal steps in the
reverse order.
Rear Axle Brake Hose
Removal Steps
1. Brake pipe
2. Clip
3. Brake pipe
4. Bolt
5. HoseInstallation Steps
To install, follow the removal steps in the
reverse order.
Page 904 of 3573

5C – 26 POWER ASSISTED BRAKE SYSTEM
REMOVAL
Preparation:
1) Raise the vehicle and support it with suitable
safety stands.
2) Remove wheel and tire assembly.
3) Clean dirt, grease, and other foreign material off
the hose fittings at both ends.
Front/Rear Caliper Brake Hose
1. Brake Pipe
2. Clip
3. Bolt and Gasket
4. Hose
Rear Axle Brake Hose
1. Brake Pipe
2. Clip
3. Brake Pipe
4. Bolt
5. Hose
INSTALLATION
To install, follow the removal steps in the reverse
order, noting the following points. After installing the
brake hoses, bleed brakes as described in this
section.
Front/Rear Caliper Brake Hose
1. Tighten the brake pipes to the specified torque.
Brake Pipe Torque N·m(kg·m/lb·ft)
16 (1.6 / 12)
2. Tighten the bolt to the specified torque.
Bolt Torque N·m(kg·m/lb·ft)
35 (3.5 / 26)
NOTE:
•Always use new copper gaskets.
•Be sure to put the hooked edge of the flexible
hose end into the anti-rotation cavity.
Rear Axle Brake Hose
1. Tighten the brake pipes to the specified torque.
Brake Pipe Torque N·m(kg·m/lb·ft)
16 (1.6 / 12)
2. Tighten the bolt to the specified torque.
Bolt Torque N·m(kg·cm/lb·in)
13 (130 / 113)