Composed of a cylinder with pistons on both sides and a rubber seal inside, the wheel cylinder is responsible for keeping the brake shoes in contact with the drum whenever you step on the pedal. Over time, this cylinder will eventually leak, causing the brakes to perform poorly. So before a leaking wheel cylinder causes a road accident, replace it as soon as you can. Here's what you need to do:
Tools you'll need:
- Jack stands
- Drip pan or any similar container
- Brake cleaner
- Brake fluid
- Brake shoe removal tool
- Brake spring tool
- Rust penetration spray
Step 1: Prep the vehicle.
Jack up your car with jacks and a jack stand on a level surface. Make sure that the jacks and jack stand are properly installed under the vehicle to avoid accidents.
Step 2: Remove the tire, brake drum, and brake shoes.
Grab a socket and wrench to loosen and remove the lug nuts that attach the wheel onto your vehicle. Once you've removed these nuts, you should be able to pull off the tire. Then remove the brake drum by removing the bolt on the center that holds it in place. The next component to remove is the brake shoes. Using a brake spring tool, dislodge the return spring. Get a good grip on the back of the retainer pin and insert the brake shoe removal tool onto the retainer clip. Remove the retainer and pin by pressing the tool down and twisting it counterclockwise.
Step 3: Disconnect the brake line.
Spray the brake line's hydraulic fitting with a bit of rust penetrating liquid to make removal an easier process. Make sure a drip pan is placed underneath to catch spilled brake fluid. Then loosen the hydraulic fitting with a wrench. Twist the wrench back and forth until the fitting is removed. Next is to remove the mounting bolts found at the back of the wheel cylinder. Once the bolts are removed, you can pull out the old cylinder with your hands.
Step 4: Install the new wheel cylinder.
Place the new cylinder in position and connect it to the brake line's hydraulic fitting. Twist it in place with your hand and mount the bolts attached to the backing plate. Tighten the bolts according to torque specifications. After mounting the cylinder bolts, tighten the brake line's fitting.
Step 5: Reinstall all the parts you've removed.
Start with the brake shoes then move on to the brake drum and wheel. Make sure all bolts and nuts are tightened according to torque specifications. Once every part is reinstalled, make sure to bleed the brakes and refill the brake fluid when necessary.
- When disconnecting the brake line, it's best to use a line wrench instead of regular one as you pull off the hydraulic fitting. This is to ensure that you don't break the fitting and the brake line.
- Depending on your car make and model, a wheel cylinder can be attached to the assembly with snap rings or clips instead of a bolt. Check with your vehicle manual so you'll know which tool to use.