FAQ: Brake Calipers

Caliper rebuilding entails the substitution of worn or impaired components. This process typically includes the replacement of pressure seals and dust boots that may have turned brittle due to aging or prolonged exposure to intense heat, particularly in instances of heavy use such as racing. On occasion, the need may arise to replace pistons that exhibit corrosion, pitting, dents, or even melting.

There isn't a strict guideline regarding the frequency of caliper rebuilding. While certain calipers may not require rebuilding throughout the vehicle's lifespan, high-performance race cars might necessitate multiple rebuilds in a single season. During each pad replacement, it is crucial to meticulously examine the calipers. A caliper rebuild is warranted in the presence of any of the following conditions:

• Dust boots may be vaporized, cracked, or have lost their soft and pliable texture

• Brake pads may exhibit dragging, leading to overheating

• Pistons may prove difficult or impossible to retract

• Brake fluid leakage may occur around one or more pistons

• Calipers are undergoing refinishing, such as stripping and painting or powder coating

It is crucial to ascertain the piston sizes within your caliper, as many calipers utilize staggered pistons to maintain parallel alignment of the pads with the rotor during braking, ensuring even pad wear.

For StopTech calipers, see: How to Measure StopTech Pistons.

For most other aftermarket calipers, you should measure piston diameter directly.