FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Disc Brakes (Front)

DESCRIPTION
The front disc brake assembly used on this vehicle consists of the following components:
^ Disc brake caliper
^ Brake Shoes (and linings)
^ Brake shoe retractor clips (except on vehicles with BR5 Performance Brake Package)
^ Brake Rotor












The floating double pin single piston calipers used on this vehicle are mounted directly to the steering knuckles and use no adapter. The caliper is mounted to the steering knuckle using bushings, sleeves and 2 thru-bolts which thread directly into the steering knuckle.
The caliper is a one piece casting with the inboard side containing a single piston cylinder bore. The front disc brake caliper phenolic piston is 60 mm (2.36 inch) in diameter.
There are two brake shoes mounted to the brake caliper. One brake shoe is mounted on each side of a brake rotor. The brake shoe lining material used has been specifically formulated to meet the braking requirements of the vehicle. An audible wear indicator is mounted on the outboard pad of the front disc brake assemblies.
Retractor clips are mounted above and below the brake pads (when mounted), except on models equipped with the performance disc brake package (BR5). The performance disc brake package (BR5) does not use retractor clips.
The brake rotor is mounted on the hub and bearing. The rotor is made of iron and is vented to help cool it during brake applications.

OPERATION

Two machined abutments on the steering knuckle position and align the caliper fore and aft. The guide pin bolts, sleeves, and bushings control the side-to-side movement of the caliper.
The disc brake calipers have shoe retractor clips attached to the inner and outer brake shoe and lining assemblies to help pull the front brake pads away from the rotor when the brakes are released. Vehicles equipped with the performance disc brake package (BR5) do not have retractor clips.
Although there are different disc brake systems available, they operate and are serviced in the same manner.

Fig. 2 Piston Seal Function:






A square cut rubber piston seal is located in a machined groove in the cylinder bore. This provides a hydraulic seal between the piston and the cylinder wall. The piston seal is designed to pull the piston back into the bore of the caliper when the brake pedal is released. This, along with the brake shoe retractor clips, maintains the proper brake shoe to rotor clearance.
A molded rubber dust boot is installed in a groove in the cylinder bore and the piston, keeping contamination from the cylinder wall and the piston.
The brake shoe lining material rides against the brake rotors braking surface. When the brakes are applied, the shoes apply pressure against the rotor, thus slowing the vehicle.
As brake shoe linings wear, master cylinder reservoir brake fluid level will go down. If brake fluid has been added to the reservoir, overflow may occur if the piston is pushed back into the recessed position.
An audible wear indicator is mounted on the outboard pad of the front disc brake assemblies. Upon contact with the brake rotor, this indicator emits a sound, signaling that brake shoes may need inspection or replacement.