Drum Brake System: Adjustments
PROCEDURENOTE: Normally, self adjusting drum brakes will not require manual brake shoe adjustment. Although in the event that the rear brake shoes are replaced it is advisable to make the initial adjustment manually to speed up the initial adjustment time.
1. Raise vehicle using a frame contact type hoist or supported as required using jack stands.
2. Remove the rubber plug from the brake adjuster access hole in the brake support plate.
3. Be sure parking brake lever is fully released.
4. Insert a thin screwdriver through the adjuster access hole in the brake support plate. Engage the tip of the screwdriver with the star wheel on the automatic adjuster. Move the handle of the screwdriver downward (toward the ground). Repeat the above procedure until drag is felt when rear wheel is rotated.
CAUTION: When performing the procedure in Step 5, care must be taken not to bend the adjuster actuating lever or distort the lever actuating spring.
5. Insert a thin screwdriver or a piece of welding rod through the adjuster access hole. Carefully push the adjuster actuating lever out of engagement with the adjuster star wheel. While holding the adjuster actuating lever away from the star wheel insert a second screwdriver in access hole and engage it with the star wheel on the adjuster. Back off the adjuster star wheel until no drag is present when rotating the wheel.
6. Repeat the above adjustment procedure at the other rear wheel.
7. Apply and release the park brake lever one time after the rear brake shoes are adjusted. This will correctly adjust the tension of the park brake cables.
8. Install the rubber plugs into the adjuster access holes in the brake support plates.
NOTE: Unique to this vehicle is a new fully automatic adjusting mechanism for the rear drum brakes. The rear drum brakes used on this vehicle have no provisions to be manually adjusted and should not require manual brake shoe adjustment for the life of the linings. Although in the event of a brake reline, it will require the automatic adjuster to be reset. After resetting the automatic adjuster the initial adjustment procedure must be done prior to driving the vehicle.
INITIAL ADJUSTMENT PROCEDURE
1. Be sure parking brake lever is fully released.
2. Fully apply the vehicles service brakes 2 to 3 times by depressing the brake pedal as far as possible. This will cause the automatic adjuster mechanism to correctly adjust the rear drum brakes.
3. Apply and release the park brake lever one time after the service brakes have been correctly adjusted.
4. This procedure has correctly adjusted the vehicle's rear service brakes.