Tools You'll Need:
* Jack and jack stands: Crucial for safety. Never work under a vehicle supported only by a jack.
* Lug wrench: To remove the wheels.
* Wheel chocks: For added safety.
* Socket wrench set (metric): Various sizes will be needed.
* Torque wrench: Essential for properly tightening bolts to prevent damage.
* C-clamp or caliper compression tool: To compress the caliper piston.
* Hammer and punch (optional): May be needed to help remove rusted or stuck components.
* Wire brush: To clean rusty surfaces.
* Penetrating lubricant (PB Blaster or similar): To loosen stuck bolts.
* New rear brake rotors: Make sure you get the correct ones for your specific vehicle.
* New brake pads (recommended): It's best practice to replace pads when you replace rotors for even wear.
* Gloves and safety glasses: Protect yourself.
Procedure:
1. Safety First: Park on a level surface, engage the parking brake, and chock the front wheels. Raise the rear of the truck securely using the jack and place it on jack stands.
2. Remove the Wheel: Remove the lug nuts and carefully take off the wheel.
3. Remove the Caliper:
* Locate the caliper bolts: These are usually on the back of the caliper.
* Apply penetrating lubricant: Spray penetrating lubricant on the bolts if they appear rusty or stuck. Let it sit for a few minutes.
* Remove the bolts: Use the appropriate socket to carefully remove the caliper bolts.
* Support the caliper: Use a bungee cord or wire to hang the caliper from something nearby. This prevents stress on the brake hose. Do *not* let the caliper hang by the brake hose.
4. Compress the Caliper Piston:
* Use a C-clamp or compression tool: Slowly and steadily compress the caliper piston to create enough space for the new rotor. You may need to twist the piston slightly as you compress it. Be careful not to damage the piston seal. Sometimes you'll need to pump the brake pedal to help free up the piston.
5. Remove the Rotor: The rotor should now slide off the wheel studs. If it's stuck, gently tap it with a rubber mallet or hammer and punch. Avoid damaging the wheel studs.
6. Clean the Hub: Use a wire brush to clean any rust or debris from the wheel hub.
7. Install the New Rotor: Slide the new rotor onto the wheel studs.
8. Install the Caliper: Reinstall the caliper and tighten the bolts to the manufacturer's specified torque.
9. Install the Wheel: Put the wheel back on and tighten the lug nuts.
10. Lower the Vehicle: Carefully lower the vehicle from the jack stands.
11. Torque Lug Nuts: Tighten the lug nuts to the manufacturer's specified torque using a torque wrench.
12. Repeat for the Other Side: Repeat steps 2-11 for the other rear wheel.
13. Pump the Brakes: Pump the brake pedal several times to ensure proper engagement.
14. Test Drive: Take a short test drive to check for proper braking performance.
Important Considerations:
* Brake Fluid: If you're replacing brake pads as well, you may need to add brake fluid as the caliper piston is compressed.
* Parking Brake: Some models have a parking brake mechanism integrated into the rear caliper. You may need to disengage this before you can remove the caliper. Consult your repair manual.
* ABS Sensors: Be careful not to damage the ABS sensor ring on the hub.
* Rust: Rust can make this job significantly more difficult. Penetrating lubricant is your friend.
This is a general overview. Refer to your vehicle's repair manual for detailed instructions and torque specifications specific to your 2002 GMC Sierra 4x4. If you're uncomfortable performing this repair, take it to a qualified mechanic. Brake safety is paramount.
