1. Safety First:
* Jack up the vehicle securely: Use jack stands, *never* rely solely on a jack. Place the stands under the frame near the front wheels.
* Chock the rear wheels: This prevents the vehicle from rolling.
* Wear safety glasses and gloves: Brake fluid is corrosive.
2. Gather Tools and Supplies:
* Jack and jack stands
* Wheel chocks
* Lug wrench
* Sockets and wrenches (sizes will depend on your specific Explorer, consult your repair manual) You'll likely need sockets for the caliper bolts and possibly a wrench for a caliper bracket bolt.
* C-clamp or caliper piston compression tool: This is crucial for retracting the frozen piston. A dedicated tool is best, but a large C-clamp *can* work with care. Improper use can damage the piston.
* Penetrating oil (like PB Blaster): This helps loosen seized parts.
* Brake cleaner: To clean the caliper and surrounding area.
* New brake pads (make sure you get the correct ones for your model)
* New caliper (possibly): If you can't free the piston, you might need to replace the caliper.
* Rags or shop towels: To clean up brake fluid spills.
* Repair manual (highly recommended): A manual specific to your 2002 Ford Explorer will show you exactly where the bolts are, torque specs, and other crucial details.
3. Procedure:
* Remove the wheel: Loosen the lug nuts before jacking up the vehicle. Remove the wheel once it's securely supported.
* Apply penetrating oil: Generously spray penetrating oil around the caliper piston, paying attention to the area where the piston enters the caliper bore. Let it sit for at least 15-20 minutes (or longer).
* Try to manually push the piston: Before using the C-clamp or compression tool, attempt to gently push the piston back into the caliper using a large flathead screwdriver or a suitable tool. If it budges, you might be lucky and able to proceed as usual.
* Use the C-clamp or piston compression tool: This is where care is vital. Do not use excessive force. The piston needs to retract evenly. If using a C-clamp, clamp it to the caliper's mounting bracket and the piston, using a piece of wood to protect the piston's surface. Gradually apply pressure, turning the C-clamp handle slowly. Regularly check for even piston retraction. If it feels exceptionally stiff, stop.
* Important Note on C-clamp method: This method can damage the piston seals and caliper if not done extremely carefully. A dedicated caliper piston compression tool is far safer and more effective. The tool rotates and retracts the piston evenly.
* If the piston does not move: You've likely exceeded the limits of gentle persuasion. The caliper likely needs to be replaced.
* Remove the caliper: Once the piston is retracted sufficiently to allow new pads to be installed, remove the caliper bolts (usually two). Be ready for some brake fluid leakage.
* Clean the caliper and caliper bracket: Use brake cleaner to thoroughly clean the caliper and bracket. Pay attention to any rust or debris.
* Install new brake pads: Insert the new brake pads into the caliper and bracket.
* Reinstall the caliper: Attach the caliper to the bracket, and ensure it's properly seated and secure. Tighten the caliper bolts to the manufacturer's specified torque.
* Bleed the brakes: After reinstalling the caliper and wheel, you *must* bleed the brakes to remove any air that may have entered the system. This is usually done using a brake bleeder kit. Consult your repair manual for the proper bleeding procedure.
* Test the brakes: After bleeding, carefully test the brakes. They should feel firm and responsive.
4. If the Piston is Truly Frozen:
If the piston absolutely will not move, even with penetrating oil and a compression tool, the caliper is likely seized and needs replacement. It's less expensive and safer to replace the caliper than to risk damaging the piston and creating further problems.
Disclaimer: This is general advice. Always consult a repair manual specific to your 2002 Ford Explorer for precise procedures, torque specifications, and safety precautions. If you are not comfortable performing this repair yourself, take your vehicle to a qualified mechanic. Improper brake repair can be extremely dangerous.
