Q: How to overhaul the rear brake calipers on 2000 Cadillac Eldorado?
A: A change of rear brake caliper can begin by removing it from the car. Finally, remove the Piston and Piston boot by installing the Piston counterclockwise using suitable long nose pliers or a Piston driver tool without the use of a metal tool on boot ring or Piston seal. Remove the boot ring from the groove at the caliper bore and the Piston seal using a small wooden or plastic tool. Then, take out the Piston boot from the Piston as well as the bleeder valve from the caliper body. It is the only part of the parking brake mechanism that can be brought out or replaced. Do not cause this mechanism to fall apart, and replace the caliper if damaged or ineffective parking brake. If the return spring of the lever is screwed, replace it. Remove the snap ring from the Piston using snap ring pliers and replace the caliper Piston if it has damaged the internal parts. Check the spacer, wave washer, spacer, ball bearings, and adjusting nut from the Piston, and clean all components using denatured alcohol, followed by their drying using unlubricated, low-pressure compressed air by passing air with all passages in the caliper body and through the bleeder valve. The Piston sliding surface is plated, therefore, avoid polishing with an emery paper. Check the Piston for scoring, rust, wear, damage, or foreign objects replacing if any problem is found. Wipe the caliper cylinder free from old brake fluid, with no mineral oil, and minor surface rust or foreign substances that may need to be polished with fine crocus cloth. Check the inside surface of the cylinder for the same issues, fixing the caliper body when it is necessary. Reassembly by the installation in the Piston of the adjusting nut, ball bearings, and then spacer, wave washer and then spacer again with the snap ring. Mount the bleeder valve to the caliper body, apply clean brake fluid to the new Piston seal and fit it into the caliper bore. Mount the new boot on the Piston, screw in the Piston into the caliper body properly using appropriate long-nosed pliers or Piston driver tool, and fit the boot ring into caliper counterbore against Piston boot before mounting the caliper back to the vehicle.