In the proper procedure for replacing disc brake pads, what is done to accommodate new pads?

• A. Open the brake fluid cap
• B. Use a brake bleeder to create vacuum
• C. Slowly bottom the piston in the caliper
• D. Remove the caliper completely

Answer: (C)

When replacing disc brake pads, it is essential to accommodate the new, thicker brake pads by adjusting the position of the piston within the caliper. The correct procedure involves slowly bottoming the piston in the caliper. This process effectively pushes the piston back into its cylinder, creating enough space for the new pads to fit in place without causing excessive friction or misalignment.

This step is crucial because if the piston is not properly recessed, the new pads may not fit correctly, leading to problems such as dragging brakes, noise, or uneven wear. Ensuring that the piston goes all the way back allows the brakes to function as intended when the new pads are installed.

Other methods, while they might seem helpful, do not specifically address the need for adjusting the piston to accommodate the new pads effectively. For example, opening the brake fluid cap can relieve pressure, but it doesn't adjust the position of the piston. Using a brake bleeder to create vacuum is not a standard part of this process and is generally used for different maintenance tasks related to brake fluid and air in the lines. Similarly, removing the caliper completely, while it might provide easier access, is not necessary to simply install new pads and can unnecessarily complicate the job.