How to Remove a Brake Piston

The braking system on your vehicle uses brake calipers to clamp down the brake pads against the brake rotor, slowing down the vehicle in the process. These calipers have at least one piston that extends or retracts with the pushing and releasing of the brake pedal. These pistons have seals around them, and those seals can break down. Should that happen, the caliper will need to be replaced or rebuilt. If you decide to rebuild the caliper, you have to remove the piston from the caliper, which takes about 30 minutes to do.

Things You'll Need

  • Jack
  • Jack stands
  • Tire iron
  • 3/8-inch ratchet and socket set
  • Line wrench
  • Air compressor
  • Rubber-tipped air blow gun
  • Wood blocks
  • Long thin punch
  • Hammer
  • Lift the vehicle up using the jack and put it on jack stands. Take off the front wheels using the tire iron and set them out of the workspace.

  • Remove the brake line running to the brake caliper using the line wrench. Unbolt the brake caliper from the brake caliper adapter bracket with the 3/8-inch ratchet and socket. Pull the caliper off of the brake rotor, then remove the brake pads from the caliper with your hands. Take the caliper and put it on a clean work surface.

  • Locate the brake pistons on the caliper, which are the circular components on the inside of the caliper. Place the wood blocks on the opposite side of the caliper from the piston so that when the pistons are removed from the caliper that they impact the wood first.

  • Connect the blow gun to the air compressor with the fitting on the air compressor's hose. Insert the rubber tip on the blow gun into the brake line port on the top of the caliper. Pull the trigger on the blow gun and hold it down as the pistons start to come out of the caliper.

  • Turn the caliper on its edge so that the piston is vertical. Insert the long thin punch into the brake line hole and strike the punch with the hammer until the piston comes all the way out of the brake caliper.