When inspection of the brake shoes shows that the linings have worn excessively, it is time to replace the brake shoes.
Linings that are attached to the shoes by rivets should be replaced when worn to within 1/32 in. of the rivet heads. Bonded linings may wear down to 1/16 in. thick. To maintain equal braking action on both sides of the car, the brakes must be serviced in pairs; that is, you must replace the brake shoes and linings on both rear wheels and both front wheels at the same time, even if you find that only one wheel of either set needs new linings.
Caution: Older brake linings contain asbestos, which is a health hazard if inhaled. Wear a face mask when working on drum brakes to avoid inhaling asbestos particles. Keep dust levels down; do not blow or vigorously brush accumulated material from brake parts.
Front Brake Shoe Replacement
- Block the rear wheels to prevent movement and apply the parking brake.
- With the wheels still on the ground, loosen the wheel lug bolts/nuts, then raise the front of the car and place it securely on jack stands.
- Remove the lug bolts/nuts the rest of the way and stow them in a safe place. Remove the front wheels.
- On the driver's side front wheel -- with a small flat-blade screwdriver (or circlip pliers if you're lucky enough to have them), remove the small circlip which holds the speedometer cable in the dust cap.
- Using a large screwdriver, pry off the dust caps that protect the wheel bearings (both wheels).
Note: We found it a lot easier to remove the dust cap with a small crowbar. Saves on the skinned knuckles, too!
- Loosen the spindle nut lockbolt with a 6mm Allen wrench.
- Using a crescent wrench, remove the spindle nut and thrust washer from the end of the spindle.
Note: The left-side spindle has left-hand threads.
- Pull the hub assembly out slightly, then push it back into its original position. This should force the outer bearing off the spindle enough so it can be removed. The outer race remains in the hub.
- Remove the outer wheel bearing.
Note: Group the various axle parts and stow them in plastic bags for cleaning later.
- Pull the brake drum and hub assembly off the spindle.
Note: If the brake drum is binding on the brake shoes, insert a brake adjusting tool through each of the two adjustment holes in the backing plate and turn the adjusters until the shoes are no longer binding.
Note: Remove the brake drum without using excessive force to avoid damage to the wheel bearings, etc. Gentle tapping around the rim with a rubber or copper-faced hammer, together with pulling by hand, will usually get the job done.
- Pull off the brake drum and wipe dust from the inside of the drum with a cloth soaked in a water/detergent solution. Follow up with an alcohol wipe to avoid rust. Avoid inhaling the dust.
- Inspect the braking surface inside the drum. If it is excessively scored, have it turned. If there is insufficient metal for turning, the drum will have to be replaced. See our Brake Drum Replacement Procedure.
- Cover the spindles with plastic bags and seal tightly to keep grit off the threads. Slosh detergent/water solution over the exposed brake assemble to remove dust.
Note: Before removing any parts: If you do not have a good diagram of the braking assembly, it would be a good idea to sketch or photograph the brake shoe assembly so that you can reinstall the components correctly. Or simply work on one wheel at a time so you have the other one for reference.
- Remove all the return springs (one upper, two lower) using brake pliers or locking pliers (vice grips). Wear goggles while doing this to protect your eyes from flying springs!
- On each brake shoe there is a spring that holds the shoe against the backing plate. The spring is held in place by a pin that goes through the backing plate, through the center of the spring, then connects to a small hold-down cup on the outer end of the spring.
-
Remove the hold-down cups and springs as follows:
- Grasp the cup at its edges with a pair of needle-nose pliers. Push the cup inward to compress the spring while keeping the pin in place by holding it on the backside of the backing plate with your finger.
- Rotate the cup with the pliers 90 degrees until the flattened top of the hold-down pin lines up with the slot in the cup.
- Release the tension on the spring and remove the cup, spring, and pin. Stow them in a plastic bag.
-
Remove the lower end of the brake shoes from the slots on either end of the adjusters, then remove the upper end of the shoes from the slots on either side of the wheel cylinder. Remove the brake shoes from the assembly.
- Inspect the brake linings for cracks, excessive wear, uneven wear patterns, etc. If the linings are defective in any way, replace them.
- Clean all the brake parts with parts-cleaning solvent or isopropyl alcohol. Get all the brake dust and grime build-up off of everything.
- Tighten the backing plate bolts if necessary (15mm). (We have never found these bolts to be loose.)
-
Inspect the wheel cylinder. If it is old or leaking, remove it per our Replacing Wheel Cylinders procedure. Disassemble the wheel cylinder and inspect the pistons and seals (even if the cylinder doesn't appear to be leaking). If any of the components are rusted, pitted, or scored, replace or rebuild the wheel cylinder.
Note: If you remove the wheel cylinders, it will be necessary to bleed the brakes when you're finished. See the
-
Perform Brake System Bleeding Procedure.
-
Using a wire brush and emery cloth, remove rust from the brake shoe contact points on the backing plate. Spread a light film of high-melting point grease on the contact points.
Note: "Dry Lube" works well for this -- a stick of hard grease that looks like a candle.
- Remove, disassemble, and inspect the adjuster screws. If they are rusted or pitted, or the adjusting star will not turn freely, replace the adjusters. Lubricate the adjuster screws with penetrating oil, wiping them "dry" afterwards. The remaining trace of oil will be enough for lubrication requirements.
- Screw the adjusting screws all the way in (brakes completely loosened) for now.
- Reverse the procedure to install the new brake shoes.
- Line up the slots in the adjusting screws to match the angle of the tab on the brake shoes and slip the brake shoes into the slots. Attach the two springs at the bottom. Be careful not to damage or distort the springs. Again, wear goggles!
-
Slip the tabs at the top of the brake shoes into the slots on either side of the wheel cylinder and attach the return spring by grasping the straight part with locking pliers (vice grips) and stretching the spring to the appropriate hole in the brake shoe.
Note: If these or any other brake springs are nicked, discolored by heat, or weak, replace them with new ones.
-
Install the new hold-down pins, springs, and cups in both shoes to secure them to the backing plate, as follows:
Note: Reinstalling the hold-down springs is more difficult that removing them.
- Make sure the cup is firmly seated in the end of the spring.
- Install the hold-down pin by pushing it through the hole in the backing plate that lines up with the hole in the shoe.
Note: It helps to have an assistant here to hold the brake shoe, and it wants to flip forward away from the backing plate. If you're doing this alone, tie a cord around the brake assembly to hold the brake shoes in place while you install the hold-down spring.
-
Grasp the hold-down cup, with the spring attached, at the edges with the needle-nosed pliers.
- With the hold-down pin protruding through the hole in the brake shoe, place the spring over the pin.
- With the pliers, turn the cup/spring assembly until the slot in the cup lines up with the flattened end of the hold-down pin.
- Compress the spring until the flat end of the pin protrudes through the cup, then turn the cup 90 degrees to secure the pin inside of it.
-
While installing the brake drum, carefully inspect the wheel bearings (cleaned per the Front Wheel Bearings Procedure for cracks, heat discoloration, worn rollers, etc). If any defects are found, replace the wheel bearings.
-
Install the brake drum and repack the wheel bearings in accordance with the above procedure.
-
Adjust the brakes according to the Brake Adjustment Procedure.
-
If necessary, bleed the brakes in accordance with the Brake System Bleeding Procedure.
- Replace the front wheels and lower the car to the ground. Fully tighten the lug bolts/nuts.
- Test drive the car and make several low-speed stops to make sure the brakes are operating properly.
- Brake linings must "wear-in," try to avoid sudden stops for the next 100 miles.
Article used with Permission: www.vw-resource.com