How to Remove Brake Calipers on Car Wheels

Disc brakes utilize a heavy disc, called a rotor. The disc is bolted to the wheel hub and the brake caliper surrounds the disc. The brake caliper is attached to the wheel spindle assembly. Brake fluid pressure from the master cylinder causes the caliper piston to move toward the disc. The seal around the piston moves sideways forcing the brake pads into the rotating disc. When brake fluid pressure decreases, the piston seal pulls the caliper piston away from the disc.Over time, the piston seals become rigid and fail to push the caliper pistons into the disc or pull the piston back when pressure is released. The driver will experience longer stopping distance and hear scraping noises coming from the affected caliper. Once you determine the caliper is not functioning properly, take the steps that follow to remove the defective part.

Difficulty: Moderate

Instructions

Things You'll Need:

• Open box end wrench (2)
• Breaker bar and 12-point socket
• Ratchet and socket set
• Wheel lock key
• Torque wrench
• Air impact wrench and socket set (optional)
• Fluid drip pan
• Safety glasses
• WD-40 (optional)
• New caliper assembly
• Hydraulic jack
• Creeper
• Large flat tip screwdriver
• Line wrench
• Face shield

1. Use a large flat tip screwdriver to remove the hub cap exposing the lug nuts. Use an impact wrench and socket or lug wrench to loosen all lug nuts on the wheel you are working on. Make sure you use the wheel lock fitting to remove the lug nut with the wheel lock.

2. Block the wheels opposite the ones you are working on. Use a hydraulic jack to raise the car up far enough to position jack stands at the jacking points. Use the service manual for your year model vehicle to locate the jacking points.

3. Let the hydraulic jack down a little at a time, once the jack stands are set under the vehicle, making sure the vehicle sits down on the jacks squarely. Remove the jack and move it out of your way.

4. Remove the lug nuts by hand or with your lug wrench. Put all the lug nuts and the wheel lock key in the hub cap to prevent losing them. Pull the tire free from the wheel hub and move out of your way.

5. Use a creeper to move under the car next to the wheel hub. Locate the caliper bolts (two) and spray WD-40 on the bolts. Allow the WD-40 to soak into the bolt threads for about 15 minutes.

6. Position the drip pan under the wheel hub. Use your line wrench and open end box end wrench to disconnect the flexible brake hose from the fitting on the caliper and brake line. Use the open end box end wrench to hold pressure on the hose and the line wrench to loosen the connection to the caliper. Do not twist the brake hose or let the caliper hang by the hose. This will cause damage to the hose and leaks later on.

7. Use your impact wrench or breaker bar and 12-point socket to loosen the caliper mount bolts. Keep one hand on the caliper (to prevent the caliper from hitting the floor). Use the other hand to unscrew the bolts. (Put them in the hub cap with the other hardware.) The caliper will now be free to remove. Observe how the break pads are installed in the caliper. This will make installation of the new parts easier.

Tips & Warnings

• Do not twist the brake hose when disconnecting it from the hard line and caliper fitting. This will damage hose and cause serious leaks.
• Safety glasses should be worn throughout this procedure.
• Caliper bolts are notoriously difficult to remove. If the breaker bar and the impact wrench cannot loosen the bolts, uUse a hand torch to heat up the caliper and bolts. Wear flame resistant mechanics gloves, safety glasses and a face shield when attempting this procedure.
• Dispose of any fluid in the drip pan in an OSHA approved container for waste oil.
• Hand torches are extremely dangerous if not handled properly. Do not operate if you are not trained in how to use it.
• If you get brake fluid in your eyes, flush with water for 15 minutes and seek medical care immediately.
• If the vehicle is not properly positioned on jackstands, the vehicle could fall and cause severe injury or death.