How to Replace Rotors

Since a brake rotor is ground against by the brake pads, it should be unsurprising that it needs care as often as the brake pad. Because of how disk brakes work, rotors can suffer deep grooves and scoring in their surfaces. While they can last longer than brake pads, they will still eventually need to be replaced.

Difficulty: Challenging

Instructions

Things You'll Need:

• Car lift
• Ratchet
• Pliers
• Hammer
• Wrench set
• Tire iron
• Dial indicator
• Brake cleaner

1. Loosen the lug nuts on the vehicle's wheels using a tire iron. You only need one or two turns to loosen them before raising the vehicle.

2. Raise the car. A standard car jack is not recommended for this, as the lack of stability poses a serious danger to the mechanic attempting to reach under the vehicle to replace the rotors.

3. Remove the lug nuts from the tire and then remove the tire itself. Store the lug nuts in a safe area to prevent loss.

4. Examine the brakes with a dial indicator to ensure the rotors are not warped or lopsided. Set the dial indicator to read zero and then attach it to the rotor. Turn the rotor, and if the dial stays close to the zero setting, the rotor will not need to be replaced, although it should still be treated.

5. Remove the brake caliper in order to gain access to the rotor. Locate the bolts that hold the brake caliper to the vehicle, and remove them with a ratchet. Do not stress the brake line attached to the caliper under any circumstances, instead using a coat hanger to suspend the brake caliper without damaging the brake line.

6. Remove the freed rotor from its position. If it needs to be replaced, take your replacement rotor and put it into position on the screw posts of the wheel assembly.

7. Make sure the rotor is clean and then reinstall the brake pads and brake caliper. If at any point you are unsure how to properly reinstall these components, use the other side of the car as a guide.

8. Check the assembly for cleanliness again, as dirt and grime can affect your braking system detrimentally. Use brake cleaner if necessary.

9. Repeat the process on the other side of the vehicle. Use the side you have just completed as a guide.

10. Replace the tire and screw on the lug nuts. Wait until the vehicle has been lowered to finish tightening them by hand.

11. Test the braking system by slowly pumping and releasing the brake pedal until it operates normally. Should the brake pedal not work properly, consult your local automobile mechanic. Operating the vehicle before the brake pedal works properly is extremely unsafe.

Tips & Warnings

• Front brake rotors will need to be replaced more often than rear brake rotors. You should also replace the front rotors as a pair at the same time in order to avoid uneven or reduced efficiency of braking. Replace rear rotors as a pair, too.