Tools You'll Need:
* Jack and jack stands (SAFETY FIRST: Never work under a vehicle supported only by a jack)
* Lug wrench
* Wheel chocks
* Socket wrench set (metric) with extensions and ratchets
* Caliper piston compression tool (C-clamp can sometimes work in a pinch, but a dedicated tool is better)
* Rotor removal tool (optional, but highly recommended to avoid damaging the rotor)
* Hammer (small, ideally a rubber mallet)
* Wire brush or brake cleaner
* Anti-seize lubricant
* New front brake rotors
* New brake pads (highly recommended to replace these at the same time)
* Torque wrench
Steps:
1. Safety First: Park on a level surface, engage the parking brake, and chock the rear wheels. Raise the front of the truck using the jack and securely support it with jack stands.
2. Remove the Wheel: Remove the lug nuts using the lug wrench. Lower the wheel and carefully set it aside.
3. Remove the Caliper:
* Locate the caliper mounting bolts: These are usually on the back of the caliper.
* Remove the bolts: Use the appropriate socket and ratchet.
* Support the caliper: Use a bungee cord or wire to hang the caliper from something nearby, preventing it from dangling by the brake line. Do not let the brake line hang freely.
4. Compress the Caliper Piston: Use the caliper piston compression tool to push the piston back into the caliper. This creates space to remove the old rotor. You'll need to turn the piston as you compress it. Be careful not to damage the piston seal.
5. Remove the Old Rotor:
* Remove the caliper mounting bracket bolts (if applicable): Some models require removal of the caliper bracket to access the rotor. Consult your repair manual.
* Use a rotor removal tool (recommended): This tool helps pry the rotor off the wheel hub. If you don't have one, you might be able to carefully tap the rotor off using a hammer, but be very gentle to avoid damaging the hub.
* Clean the hub: Use a wire brush to remove any rust or debris from the wheel hub mating surface.
6. Install the New Rotor: Slide the new rotor onto the wheel studs. Ensure it sits flush against the hub.
7. Reinstall the Caliper: Carefully reinstall the caliper and its mounting bolts (and bracket if applicable), tightening them to the manufacturer's specified torque.
8. Reinstall the Wheel: Mount the wheel and tighten the lug nuts in a star pattern (opposite nuts first, then the ones in between). Don't overtighten yet.
9. Lower the Vehicle: Lower the vehicle to the ground.
10. Torque the Lug Nuts: Tighten the lug nuts to the manufacturer's specified torque using a torque wrench.
11. Repeat for the Other Side: Repeat steps 2-10 for the other front wheel.
12. Test the Brakes: Before driving, carefully test your brakes several times to ensure they function correctly. It may take some time for the new pads and rotors to fully seat.
Important Considerations:
* Brake Fluid: If you are replacing the brake pads, you might need to bleed the brakes afterward to remove any air that may have entered the system.
* Rust: If the rotors or calipers are severely rusted, you might need penetrating oil to help loosen them.
* Torque Specifications: Always refer to your vehicle's repair manual for the correct torque specifications for all bolts and nuts. Using the wrong torque can lead to damage or failure.
* Professional Help: If you're uncomfortable performing this repair yourself, it's best to take your vehicle to a qualified mechanic. Brake system work is critical for safety.
This guide provides general instructions. Always consult your vehicle's repair manual for specific instructions and torque specifications relevant to your 1998 GMC Sierra. Incorrect procedures can lead to brake failure and serious injury.
