To check disc brakes, follow these steps:
1. Jack up your vehicle and remove a front wheel. Use wheel blocks for safety.
2. Look at the brake disc (also called a rotor), but don’t attempt to remove it from the vehicle.
The brake caliper has to be removed before you can remove a brake disc, and the good news is that there’s no need to do so. If you’re working alone, just check the visible part of the disc for heavy rust, scoring, and uneven wear. Rust generally is harmless unless the vehicle has been standing idle for a long time and the rust has really built up. If your disc is badly scored or worn unevenly, have a professional determine whether it can be reground or needs to be replaced.
3. Inspect your brake caliper (the component blocking your view of the entire brake disc). Be careful. If the vehicle has been driven recently, the caliper will be hot. If it’s cool to the touch, grasp it and gently shake it to make sure that it isn’t loosely mounted and its mounting hardware isn’t worn.
4. Peek through the inspection hole in the dust shield on the caliper and look at the brake pads inside.
If the linings on the brake pads look much thinner than the new ones you saw at the supply store or dealership parts department, they probably have to be replaced. If the linings have worn to the metal pads, the disc probably has to be reground or replaced as well.
5. Replace your wheel, lug nuts, and hubcap, and lower the vehicle to the ground. If the disc and pads seem to be in good condition and your brake pedal doesn’t flutter when you step on it, you don’t need to do anything else.