How to Change Brakes & Rotors on a 2004 GMC Sierra

The brake system on the 2004 GMC Sierra consists of components such as brake pads, brake calipers and brake rotors. Each of these components work in conjunction with the others to bring the Sierra to a stop: When the driver pushes on the brake pedal, the brake fluid pressurizes against the cylinder inside the brake caliper; the cylinder then pushes the outer brake pad towards the brake rotor; finally, once the outer brake pad is compressed to the back of the brake rotor, the inner brake pad compresses to the front of the brake rotor to stop the vehicle. You will have to change any of these components of the brake system when they no longer function properly.

Instructions

Park the 2004 GMC Sierra on level ground, giving yourself plenty of working room.

Loosen the lug nuts on the driver's side front wheel, using the tire tool, then loosen the lug nuts on the passenger's side front wheel.

Slide the jack under the front of the 2004 GMC Sierra. Position the jack under the cross-frame, beneath the engine. Jack the front of the Sierra up, and as soon as the truck is high enough, place the safety jack stands under each designated jacking point, behind each front wheel; then, slowly lower the Sierra until the jacking point is on top of the jack stands. Leave the jack in the "Up" position.

Remove the front driver's side wheel and the passenger's side wheel. Place both wheels near the front of the Sierra.

Move back to the driver's side front wheel and locate the upper and lower bolts on the back of the brake caliper. Remove the upper and lower caliper bolts with a 1/2-inch drive ratchet and a socket. Place the flat-head screwdriver between the outer brake pad and the outer face of the brake rotor. Wiggle the screwdriver back and forth, until the brake caliper loosens its grip of the brake rotor.

Slide the bottom of the caliper straight up, until the top of the caliper comes off the rotor, then attach the brake caliper to the steering knuckle located directly behind the wheel hub. This will prevent the brake caliper from hanging by the brake line.

Pull the inner brake pad out of the caliper, then position the C-clamp inside the caliper facing the outer brake pad. Slowly, compress the outer brake pad against the caliper cylinder by turning the C-clamp clockwise. Continue compressing the cylinder until it has fully retracted inside the caliper housing.

Unscrew the C-clamp and remove it from the brake caliper. Pull the outer brake pad out of the caliper, along with any other braking hardware. Install the new brake pads into the brake caliper along with any new braking hardware, such as any clips or shims.

Tap the back side of the brake rotor with the rubber mallet (Tap the back of the brake rotor in different areas each time that you tap it with the mallet.) Continue tapping the brake rotor until it loosens enough be pulled off the wheel studs. Pull the brake rotor straight off the wheel studs, using your hands.

Push the new brake rotors onto the wheel studs until the brake rotor is completely seated on the back of the wheel hub. Slide the brake caliper with the new brake pads back onto the brake rotor. Screw the rear caliper bolts back in and tighten then securely with the ratchet and socket.

Follow the same exact steps outlined above for replacing the brakes and rotors on the front passenger's side, the rear driver's side and the rear passenger's side wheels. Once that you have finished installing all of the brake pads and rotors, the new brake pads will have to be set to the new brake rotors.

Crank the engine and pump the brake pedal in and out five or six times to set the new brake pads to the proper distance from the new brake rotors. Turn the engine off. Jack the 2004 GMC Sierra back up and remove all of the jack stands. Lower the Sierra back to the ground. Open the hood and check the brake fluid level in the brake fluid reservoir. Add brake fluid, if necessary.