Wheel cylinders on drum brakes are the components that press the brake shoes against the drums to stop the vehicle. Wheel cylinders have internal seals that are covered by dust boots and these seals go bad and leak with age. When these seals go bad, replacement of the cylinder is required. The replacement process can be done on your own, as long as you know the proper steps to take.
- Skill level:
Things you need
- Socket set
- Torque wrench
- Line wrench set
- Floor jack
- Drum brake spring tool
- Needle nosed pliers
- Jack stands
- Torque wrench
- Repair manual (Chilton's or Haynes)
Jack up the rear of the vehicle and secure it with jack stands.
Loosen the lug nuts using a ratchet and socket. Remove the lug nuts and pull the wheel from the vehicle.
Hammer the brake drum to loosen it up and pull the drum off of the vehicle.
Use a line wrench to loosen the brake line leading into the rear of the wheel cylinder. Pull the line from the wheel cylinder.
Press the shoe hold down spring using the drum brake spring tool and turn it until the spring is released from the shoe.
Remove the upper return springs using needle nosed pliers to unhook them from the shoes.
Pull the tops of the shoes away from the wheel cylinder.
Use a ratchet and socket to loosen the bolts at the rear of the wheel cylinder. Remove the wheel cylinder by pulling it from the brakes with your hand.
Place the new wheel cylinder in the brake system and tighten the bolts with a ratchet and socket.
Put the brake line into the wheel cylinder and tighten it with a line wrench.
Place the brake shoes back onto the new wheel cylinder and hook the upper return springs to the top of the shoes. Use the needle nosed pliers to hook the springs. Make certain to line up the brake shoe frames with the notches on the wheel cylinder.
Place the hold down springs back into place using the drum spring tool. Turn the spring until it is secured to the shoe.
Push the drum back onto the brake assembly using your hands.
Bleed the air from the side where you just replaced the wheel cylinder. Bleed the brakes by pressing the pedal until it becomes firm and then loosening the bleeder valve with the line wrench. Air will flow from the bleeder valve. Repeat this step until only fluid flows from the bleeder valve.
Place the wheel back on the vehicle and hand-tighten the lug nuts. Lower the vehicle to the ground.
Torque the lug nuts to the manufacturer specifications listed in the repair manual. Use the torque wrench and socket to torque the wheels.