1. Safety First: Engage the parking brake firmly. Chock the front wheels. Wear safety glasses.
2. Remove the wheel: Loosen the lug nuts before jacking up the car and removing the wheel.
3. Remove the caliper: You'll likely need to remove the caliper mounting bolts (usually two). Once loose, carefully support the caliper with a bungee cord or wire attached to something stable near the suspension. Don't let the caliper hang by the brake hose.
4. Remove the brake pads: The old brake pads will slide out from between the caliper and the rotor.
5. Compress the caliper piston: This is where the screw-type design comes in. There's usually a small square hole or a recess on the back of the caliper piston. You'll need a special tool for this; a C-clamp or caliper piston compression tool is what you'll typically use. Do not use a screwdriver or anything that could mar the piston's surface.
* Insert the tool: Insert the compression tool into the hole or recess on the piston.
* Turn and compress: Slowly and steadily turn the tool, compressing the piston back into the caliper. You'll need to turn it quite a few times, depending on how much you've worn the brake pads. Be aware that the piston will turn as you compress.
* Go slowly: Do this gradually to avoid damaging the piston seals. If you meet resistance, stop and check for obstructions. You may need to use a small amount of penetrating oil (like PB Blaster) before continuing.
6. Install new pads: Carefully install the new brake pads, ensuring they are seated correctly.
7. Reinstall the caliper: Mount the caliper back onto the mounting bracket and secure with the bolts.
8. Reinstall the wheel: Tighten the lug nuts before lowering the car to the ground.
9. Pump the brakes: Pump the brake pedal several times to re-establish pressure and check the pedal feels firm. If the pedal feels soft, you may need to bleed the brakes.
Important Considerations:
* Caliper condition: Inspect the caliper for any signs of damage or leaks.
* Brake fluid: Make sure you have enough brake fluid in the reservoir. The fluid level will drop as you compress the piston. If the reservoir is low, you'll need to top it off.
* Bleeding brakes (potentially): While not always necessary, some brake fluid might have been pushed out of the system. If the pedal feels soft after reassembly, you may need to bleed the brakes to remove air bubbles.
* Special tools: You'll definitely need a suitable caliper piston compression tool. A generic "C-clamp" might work, but specialized tools will be less likely to damage the caliper piston.
If you're not comfortable performing this repair yourself, it's best to take your vehicle to a qualified mechanic. Improperly done brake work is dangerous.
