Tools and Materials:
* New front brake rotors: Ensure you get the correct size and type for your vehicle.
* New front brake pads: It's highly recommended to replace these at the same time as the rotors for optimal braking performance.
* Wheel chocks: Essential for safety.
* Jack and jack stands: Never work under a vehicle supported only by a jack.
* Lug wrench: To remove and tighten lug nuts.
* Torque wrench: Crucial for tightening lug nuts and caliper mounting bolts to the correct specification (consult your repair manual).
* Socket wrench set (metric): Various sizes will be needed.
* C-clamp or caliper compression tool: To compress the brake caliper piston.
* Wrench or socket to remove caliper mounting bolts.
* Brake cleaner: To clean the mating surfaces.
* Gloves: To protect your hands.
* Safety glasses: To protect your eyes.
* Repair manual: Highly recommended for specific torque specifications and procedures.
Procedure:
1. Safety First: Park on a level surface, engage the parking brake, and chock the rear wheels.
2. Remove the Wheels: Loosen the lug nuts slightly before jacking up the vehicle. Jack up the front of the vehicle and securely place it on jack stands. Remove the lug nuts and carefully remove the wheels.
3. Remove the Caliper:
* Use the appropriate wrench or socket to remove the caliper mounting bolts.
* Carefully support the caliper with a bungee cord or wire to prevent it from dangling and damaging the brake hose. Some people prefer to hang it from the suspension using a wire.
* Using a C-clamp or caliper compression tool, slowly compress the brake caliper piston. This creates space to accommodate the thicker new rotor. Be careful not to damage the piston seal. You may need to pump the brake pedal a few times to help the piston retract.
4. Remove the Old Rotor:
* The old rotor may be held on by small screws, or it might simply slide off once the caliper is removed. Your Jeep may use a retaining clip. Consult your repair manual to determine the specific method for your vehicle.
* Clean the wheel hub mounting surface thoroughly with brake cleaner.
5. Install the New Rotor:
* Carefully slide the new rotor onto the wheel studs. Ensure it sits flush against the hub.
6. Install the Caliper:
* Carefully install the caliper, making sure the pads make good contact with the new rotor.
* Tighten the caliper mounting bolts to the torque specification found in your repair manual.
7. Install the Wheel:
* Carefully mount the wheel and tighten the lug nuts hand-tight.
8. Lower the Vehicle:
* Lower the vehicle to the ground and tighten the lug nuts fully using the torque wrench. Do not overtighten.
9. Repeat for the Other Side: Follow the same steps for the other front wheel.
10. Pump the Brakes: After replacing both rotors and calipers, pump the brake pedal firmly several times to restore brake pressure. You may need to bleed the brakes if you had to fully remove and compress the caliper pistons. Consult your repair manual on proper brake bleeding procedures.
11. Test Drive: Take a short test drive to ensure the brakes are functioning correctly. Be cautious and gentle at first. Listen for any unusual noises.
Important Considerations:
* Repair Manual: A repair manual specific to your 1999 Jeep Grand Cherokee is invaluable. It will provide detailed instructions, torque specifications, and diagrams.
* Brake Bleeding: If you completely removed the calipers, you'll likely need to bleed the brakes. This is a crucial step to remove air from the brake lines.
* Rust and Corrosion: If the bolts are rusty or seized, you may need penetrating oil and some patience to loosen them.
* Caliper Condition: Inspect your calipers for damage or leaks while you have them off. Replace if necessary.
This is a complex procedure with the potential for serious injury if not done properly. If you're not comfortable with any aspect of this job, it's best to seek professional help from a qualified mechanic. Remember to always prioritize safety!
