Specifications, General Information

Type
Hydraulic, with vacuum booster
Front brake assemblies
Disc, ventilated
Rear brake assemblies
Disc or drum
Parking brake
Mechanical operation
Brake pedal
Free play, mm
1.6 ÷ 4.8
Height, mm
Models with MT
165.1
Models with AT
168.3
Parking brake lever travel, mm
Disc brake assemblies
152 ÷ 229
Drum brake assemblies
102 ÷ 178
Clearance between vacuum booster pushrod and master cylinder piston (at 508 mm Hg vacuum on booster), mm
0.0 ÷ 0.5
Disc brake assemblies
Minimum allowable brake pad thickness
Refer to Chapter Adjustments and Routine Maintenance
Minimum allowable rotor thickness
Refer to marking on rotor
Maximum allowable rotor thickness variation (parallelism), mm
0.015
Maximum allowable rotor runout, mm
0.102
Drum brake assemblies
Minimum allowable brake shoe lining thickness
Refer to Chapter Adjustments and Routine Maintenance
Maximum allowable brake drum inside diameter
Refer to marking on drum
Threaded connection tightening torques
N•m
Common brake system fasteners
Hollow banjo bolt for brake hose connection to brake caliper (front or rear)
34
Master cylinder nuts
14.9
Front strut tower brace nuts
22
Brake booster mounting nuts
12.4
Wheel speed sensor bolts
9.9
Front disc brake assemblies
Caliper bolts
4-cylinder models
73
V6 models
49
Caliper anchor bracket bolts
108
Rear disc brake assemblies
Caliper bolts
26
Caliper anchor bracket bolts
38
Rotor-to-hub screws
9.5
Rear drum brake assemblies
Wheel cylinder nuts
9.0

All models covered in this Manual are equipped with a hydraulic brake system with vacuum assist. Front wheels always use disc brake assemblies, while rear wheels may use either disc or drum brake assemblies.

All brake assemblies are equipped with self-adjusters. Brake pad wear on the front and rear disc brakes is compensated automatically, while the rear drum brakes are fitted with special adjusting devices. These devices are activated during braking and when the parking brake is applied.

The dual design of the master cylinder, which has two separate reservoirs, divides the hydraulic circuit into two independent circuits. If one circuit fails, the other continues to operate normally and provides adequate braking. The hydraulic circuits are arranged diagonally. Failure of either circuit reduces braking efficiency and causes the warning lamp on the instrument panel to illuminate when the brake pedal is depressed.
Master Cylinder
The master cylinder is mounted on the brake booster assembly, which is attached to the rear bulkhead of the engine compartment. A large brake fluid reservoir with a plastic cap is located on top of the cylinder. The reservoir is secured to the cylinder by grommets and a cylindrical pin.

As noted above, the master cylinder has a dual design that provides two independent hydraulic circuits. Fluid pressure in each circuit is generated by a separate piston inside the master cylinder.
Pressure Regulator
The pressure regulator valve assembly is mounted on the rear bulkhead of the engine compartment, near the master cylinder. It limits hydraulic pressure to the rear brake assemblies to prevent premature rear wheel lock-up during hard braking. The valve does not restrict pressure increase in the rear brake hydraulic circuits until pressure reaches a certain threshold value. Above this value, further pressure increase is limited.

The regulator is a non-serviceable component. If it fails, replace the complete assembly.
Vacuum Brake Booster
The booster uses the vacuum created in the intake manifold to increase the effectiveness of the hydraulic brake system. The vacuum booster unit is mounted on the rear bulkhead of the engine compartment.
Parking Brake
The parking brake lever is located in the passenger compartment and acts on a control rod, to which a pair of cables is attached (one for each rear brake assembly). On models with rear drum brakes, applying the lever pulls the cables, which move the actuating levers attached to the brake shoe assemblies in both rear wheel brakes. The shoes spread apart and press against the drum friction surface. On models with rear disc brakes, the levers are connected to screw-type actuators in the caliper housings. The levers act on the caliper pistons, forcing the pads against the brake discs.
Precautions
The following special precautions must be observed when servicing vehicle brake system components:

a) Use only DOT 3 brake fluid to fill the brake system.
b) Brake pad/shoe friction linings may contain asbestos, which is harmful to health. Avoid inhaling brake dust. Do not blow off dust with compressed air. Use only approved cleaning solvents to clean brake components.
c) Observe all specified tolerances and fastener tightening torques. Use only serviceable tools when working on components. If in doubt, consult a specialist. Remember that proper brake operation is essential for safe driving.
d) If there is any sign of malfunction in the brake system, stop vehicle operation immediately.