How to Replace a Brake Disc

The caliper holds the brake pads and is mounted over the brake disc or rotor.

Steel discs are widely used in brake assemblies. You will find brake discs on the front wheels--and sometimes on the rear wheels--of most cars on the road. The brake disc-also called a rotor--uses friction from the brake pads to slow down or stop the vehicle when you depress the brake pedal. Due to years of service or problems on the brake system, rotors may develop thickness variation, scores and cracks, creating very unsafe driving conditions. If you need to replace a brake disc, just follow these simple steps and have your car ready to go back on the road in a matter of minutes. Let’s go.

Things You'll Need

• Wheel lug wrench
• Jack and jack stand
• Ratchet and socket set
• C-clamp
• Torx bit set to use with a ratchet

Instructions

1. Park the car in a safe place. Using a wheel lug wrench, loosen the lugs of the wheel with the bad rotor. Do not remove the lugs.

2. Lift the car with a jack to suspend the wheel you will be working on.

3. Remove the wheel lugs and tire.

4. Push the caliper piston back into its cylinder using a medium-sized C-clamp. With the end of the screw of the C-clamp against the backing of the braking pad facing you and the other end of the clamp on the back of the caliper, screw in the C-clamp until the caliper piston is pushed back inside its cylinder.

5. Remove the back pins---using a ratchet with a socket or torx bit--that hold the brake caliper in place.

6. Remove the caliper from the brake disk and support it on a piece of wire--do not leave it hanging or the brake hose may be damaged.

7. Remove the caliper mounting bracket if necessary and the bolts that hold the brake disc in place--on some brake systems, the bracket is out of the way and the brake disc is not bolted to the wheel assembly.

8. Remove the brake disc. Install the new unit, caliper mounting bracket, caliper and tire.

9. Tight the wheel lugs just enough to hold the tire firmly in place. Lower the vehicle and finish tightening the wheel lugs.

Tips & Warnings

• If you change one of the brake discs on your car, inspect the other rotor as well. Make sure it is in good condition and just as thick as the new unit; otherwise, your vehicle will pull to one side every time you apply the brakes.