How to Change BMW Rotors

1. Make sure the vehicle is parked on a flat level surface. Ensure that the car is in gear or in Park. Use a lug wrench to loosen the lug bolts for the wheels. Raise the car with a floor jack and lower it onto jack stands at all four corners. The jacking points will differ depending on the model of BMW that you are working on. Consult your owner's manual for the proper jacking points. Remove the wheels and set them aside.
2. Clean the brake rotor, the caliper and any nearby parts with brake cleaner and a clean, dry rag, ensuring that there is no oil or residue on the brake parts. Loosen the two large bolts that hold the caliper to the carrier. These are located on the upper and lower part of the caliper facing the wheel arch. On most newer BMWs these bolts are Torx-shaped bolts that are removed with a star-shaped bit. Some older models use a normal bolt. Slide the caliper off of the rotor and support it with a piece of wire or on a platform while you work to avoid damaging the soft brake line.
3. Remove the two bolts that hold the caliper bracket on. These are located on the top and bottom of the bracket facing the wheel arch. Set the bracket aside. Remove the set screw that holds the rotor on. If it is frozen and will not loosen easily, spray penetrating fluid on it and let it soak in. The set screw is removed with a small Allen bit on BMWs. Make sure you use the properly sized tool to avoid stripping the screw. Pull the rotor straight off of the hub, tapping it from behind if needed to free it. Spray the hub mounting surface with brake cleaner and wipe it down.
4. Clean the new rotor with brake cleaner and a clean rag. Avoid touching it with your bare hands. Slide it onto the hub and reinstall the set screw. Tighten the set screw firmly. Bolt the caliper carrier back on and tighten the bolts. On most BMWs, the outer brake pad fastens to the slots in the caliper carrier and the other one clips into the piston in the caliper. If they have fallen out, reinstall them and slide the caliper and brake pads over the rotor. Tighten the bolts that hold the caliper on. Repeat the above steps for the other three corners of your BMW. Replace the wheels and lower the car to the ground. Pump the brakes until the pedal feels firm.