Foundation brake hardware includes which items?

• A. S-cams, rollers, and brake spiders
• B. Calipers and pistons
• C. Master cylinder components
• D. Wheel cylinders and shoes

Answer: (A)

In drum brake systems, the foundation brake hardware is the set of non-friction parts that position and actuate the brake shoes inside the drum. The S-cam is the rotating component that, when it turns, pushes the shoes outward. The rollers ride on the ends of that cam to make the shoe movement smooth and even. The brake spider is the support structure that holds the shoe assembly in place on the backing plate and connects to the cam mechanism. Together, these parts comprise the hardware that makes the drum brake function.

Calipers and pistons belong to disc brakes, not foundation drum-brake hardware. Master cylinder components are part of the hydraulic system, not the mechanical hardware that positions the shoes. Wheel cylinders and shoes include a hydraulic actuator and the friction elements, respectively, rather than the hardware that positions and actuates the shoes. So the described trio—S-cams, rollers, and brake spiders—is the correct set for foundation brake hardware.