Disc Brake System: Testing and Inspection

NOISE - Brake friction materials inherently generate noise and heat in order to dissipate energy. As a result, occasional squeal is possible, which may be aggravated by severe environmental conditions such as cold, heat, rain, snow, salt and mud.

SET UP
1. Raise and support vehicle.
2. Remove wheels and tires.
3. When inspection and service or repair is complete, reinstall wheel assemblies and torque lug nuts to proper specifications.

CALIPER
^ Visually check disc brake caliper. If caliper housing is leaking, it must be replaced.
^ If a seal is leaking, disc brake caliper must be disassembled and new seals and dust boot installed.
^ If caliper piston is seized in the bore, a new disc brake caliper is required.
^ Inspect locating pin boots in front disc brake caliper anchor plate to make sure they are sealed in groove. Replace damaged boots. Locating pin boots that are not properly sealed may cause disc brake caliper locating pin to corrode and brakes to drag.

BRAKE SHOE AND LININGS
^ Replace any brake shoe and lining that has been contaminated with oil, grease, or brake fluid with a complete axle set. Inspect for and correct any source of contamination.
^ Inspect brake shoe and lining for excessive wear.
^ If lining is worn to within 3 mm (1/8 inch) of shoe, replace all four brake shoes and linings (complete axle set) as necessary.

ROTOR
^ Brake pulsation (brake roughness) that is present during brake application is caused by;
- foreign material build-up
- contamination on the rotor surface
- uneven lateral runout.
^ For diagnostic procedures, refer to Brakes - System Diagnosis. Testing and Inspection