A brake job, or changing your brake pads, is a great do-it-yourself job. Before you begin, it's important to remember that the brakes are the single most important system in your car. Take plenty of time to familiarize yourself with them before you begin to work. Also, it's a good idea to work on one side at a time in case you have trouble. That way, you have one side to use as a reference. We'll assume that you want to know how to change the front disc brakes on your car since front brakes provide most of the stopping power.
Preparation for brake pad replacement:
You'll need to buy brake pads before you begin this project. Make sure they come with an anti-squeal device such as a shim, or buy some specially made fluid to add to the back of the brake pads.
Brake pads come in several different flavors. The cheap pads generally wear out faster and leave an unsightly black dust on your front wheels. More expensive pads leave less dust, but they may be more prone to squealing if they are harder pads.
Change your brake pads:
- Set the parking brake, and block the rear tires so that the car cannot move.
- Loosen the lug nuts.
- Raise the car with a jack and place it securely on jackstands.
- Remove the lug nuts and remove the wheel.
- Now you can see the brake calipers holding the brake pads in place against the rotor. There are two pads per wheel that squeeze the rotor. Use a C-clamp to compress the caliper piston into the caliper housing. This will make it possible to remove the caliper assembly, and it creates a space for the increased pad width of the new brake pads.
- Unbolt the caliper mounting bolts to and pull the caliper back from the rotor. Be careful not to bend or break the brake hose. Sometimes the caliper mounting bolts require you to use a torx or star bit instead of a normal socket set. Plan ahead and make sure you have the right tool for the job to save yourself a trip back to the parts store.
- Remove the brake pads from the caliper. Examine them for unusual or uneven wear. Is only one pad wearing down? Are the pads wearing at an angle? These could be signs of problems that need to be addressed immediately.
- This is also a good time to examine the condition of the rotors. If they have deep grooves, or if you have noticed that the car shudders when you hit the brakes, then you will need to get the rotors turned or replaced.
- Install the new brake pads in the caliper. Usually, it's best to place the inner pad first, then the outer pad second. You may have to depress the piston fully into the caliper housing in order to provide enough space for the new pads.
- Once the pads are properly seated in the caliper, put the caliper back on the rotor and bolt it firmly in place.
- If everything is correct, you may put the wheel back on, hand tighten the lug nuts, and lower the car to the ground. Finish tightening the lug nuts in a star pattern so that they are even.
Test your brakes! Carefully check your brakes and brake fluid levels before entering traffic. Sometimes some air can get into the brake lines when you change the brake pads. If this happens, you will need to bleed the brakes before you try to move the car again.
Caution: Some brake pads contain asbestos, which is a known carcinogen. Do not inhale.