REAR WHEEL DRUM BRAKES

DESCRIPTION

Rear wheel drum brakes (Figs. 2 and 3) are two shoe, internal expanding type with an automatic adjuster screw assembly that is activated each time the brakes are applied. The automatic adjuster screw is located directly below the wheel cylinder as shown in figure (Figs. 2 and 3).

WARNING: DUST AND DIRT ON BRAKE PARTS GENERATED DURING THE NORMAL USE AND WEAR OF MOTOR VEHICLE BRAKE SYSTEMS CAN CONTAIN ASBESTOS FIBERS. BREATHING EXCESSIVE CONCENTRATIONS OF ASBESTOS FIBERS CAN CAUSE SERIOUS BODILY HARM, SUCH AS ASBESTOSIS AND CANCER. EXTREME CARE SHOULD BE EXERCISED WHILE SERVICING BRAKE ASSEMBLIES OR COMPONENTS.

DO NOT CLEAN BRAKE ASSEMBLIES OR COMPONENTS WITH COMPRESSED AIR OR BY DRY BRUSHING; USE A VACUUM CLEANER SPECIFICALLY RECOMMENDED FOR USE WITH ASBESTOS FIBERS. IF A SUITABLE VACUUM CLEANER IS NOT AVAILABLE, CLEANING SHOULD BE DONE WET USING A WATER DAMPENED CLOTH.

DO NOT CREATE DUST BY SANDING, GRINDING, AND/OR SHAVING BRAKE LININGS OR PADS UNLESS SUCH OPERATION IS DONE WHILE USING PROPERLY EXHAUST VENTILATED EQUIPMENT.

DISPOSE OF ALL DUST AND DIRT SUSPECTED TO CONTAIN ANY ASBESTOS FIBERS IN SEALED BAGS OR CONTAINERS TO MINIMIZE DUST EXPOSURE TO YOURSELF AND OTHERS.

FOLLOW ALL RECOMMENDED PRACTICES PRESCRIBED BY THE OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION AND THE ENVIRONMENTAL PROTECTION AGENCY. FOR THE HANDLING, PROCESSING, AND DISPOSITION OF DUST OR DIRT WHICH MAY CONTAIN ASBESTOS FIBERS.

SERVICE PROCEDURES

REAR BRAKE DRUM REMOVAL

Further clearance can be obtained by backing off the brake automatic adjuster screw. Remove rubber plug from the top of the support plate and rotate the

automatic adjuster screw assembly with an upward motion, using the Brake Adjuster, Special Tool C-3784.

See adjusting rear service brakes in the Service Adjustments section in this group of the service manual for the specific adjustment procedure.

Remove wheel bearing grease cap (Fig. 1).

Remove cotter pin, lock nut, retaining nut and washer (Fig. 1).

Remove brake drum and hub and bearing assembly from the rear spindle (Fig. 1).

Inspect brake linings for wear, shoe alignment and contamination.

Fig. 1 Brake Drum and Hub Assembly

BRAKE DRUM INSTALLATION

Install brake drum and hub and bearing assembly on rear spindle.

Install outer wheel bearing, thrust washer and nut. Tighten wheel bearing adjusting nut to 27 to 34 NIm (240 to 300 in. lbs.) torque while rotating hub.

This seats the bearings.

Back off adjusting nut 1/4 turn (90°) then tighten adjusting nut finger tight.

Position lock on nut with one pair of slots in-line with cotter pin hole. Install cotter pin.

Install grease cap and wheel and tire assemblies. Tighten wheel stud nuts to 129 NIm (95 ft. lbs.) torque on all models. Install wheel covers.