Removal & Installation
See Figures 1 through 15
A brake spring removal tool and a brake adjusting gauge are required for this procedure.
- Raise and support the vehicle safely with jackstands.
- If the brakes have never been serviced before, the drums will be held on the wheel studs with spring nuts. Remove the spring nuts and discard.
- Turn the adjustment starwheel so that the brake shoes are retracted from the brake drum and remove the brake drum.
- Install wheel cylinder clamps to retain the wheel cylinder pistons in place and prevent leakage of brake fluid while replacing the shoes.
- Remove the U-clip and washer securing the adjuster cable to the parking brake lever.
- Remove the adjuster cable, cable guide, adjuster lever and adjuster springs. Remove the return springs with a brake spring remover tool.
- Remove the hold-down retainers and springs, then remove the brake shoes.
- Clean the backing plate with a brush or cloth. Place a dab of Lubriplate® on each spot where the brake shoes rub on the backing plate.
Always replace brake linings in axle sets. Never replace linings on one side or just on one wheel.
- Thoroughly clean and lubricate the adjuster cable guides, adjuster screw and pivot, parking brake lever and lever pivot pin with multi-purpose grease.
- Apply a thin coat of multi-purpose chassis lube to the mounting pads on the backing plate.
- Transfer the parking brake actuating lever to the new secondary shoe.
- Position the brake shoes on the backing plate, then install the hold-down springs and retainers. Don't forget to engage the parking brake lever with the cable.
- Install the parking brake actuating bar and spring between the parking brake lever and primary shoe.
- Install the self-adjusting cable, cable guide and upper return springs.
- Thoroughly clean the starwheel and lightly lubricate the threads with lithium based grease.
- Install the starwheel.
- Install the self-adjusting cam and lower spring. A big pair of locking pliers is good for this job.
- Check the surface of the brake shoes for any grease that may have gotten on them. If dirty, lightly clean with a piece of sandpaper.
- Adjust the brakes, install the brake drum and wheel. Lower the vehicle and test drive.
These brakes are equipped with self-adjusters and no manual adjustment is necessary, except when brake linings are replaced. After replacing the brake shoes, perform the following adjustment procedure:
- Insert the brake gauge in the drum and fully expand until the gauge inner legs contact the drum braking surface. Then lock the gauge in position.
- Reverse the gauge and install it on the brake shoes. Position the gauge legs at the shoe centers. If the gauge does not have a light drag fit, adjust the shoes.
- Pull the starwheel away from the automatic adjuster lever. Turn the starwheel by hand to expand or retract the shoes and recheck with the brake gauge.
- Install the brake drums, lower vehicle and make final adjustment.
- Final adjustments on drum brakes take advantage of the systems self-adjustment mechanism. Drive the vehicle and make one forward stop followed by on reverse stop. Repeat the procedure 8-10 times to equalize adjustment between the two sides. Bring the vehicle to a complete stop each time. Rolling stops will not activate the self-adjuster mechanism