Brakes

Brakes are among the most important safety systems on a vehicle. Inspecting them twice a year for wear and damage can help protect you and your passengers while identifying problems before they become more expensive.

Brake System Components That Can Fail

The master cylinder is the heart of the braking system. It holds brake fluid when the fluid is not being delivered to the brakes through the brake lines. If a worn master cylinder leaks, or if brake lines become blocked or broken, fluid cannot be delivered properly and the brake pads may be damaged.

Brake fluid can become dirty or contaminated as it absorbs moisture and collects debris. It can also deteriorate because of excessive heat. Clean brake fluid is clear or slightly yellow, while dirty fluid may appear brown or black. Old or contaminated fluid can cause internal damage to an anti-lock braking system.

Brake lines connect to the master cylinder through a combination valve containing metering and proportioning functions. This valve regulates pressure at the front and rear wheels so both sets of brakes engage appropriately. A malfunctioning combination valve may cause the wheels to lock.

Brake pads and shoes may be made from ceramic, metallic, or organic materials. The disc rotors and drums they press against are metal. Because pads and shoes rely on friction to stop the vehicle, they gradually wear down. If they wear away completely, metal components may grind against the rotors or drums and cause further damage.

Some brake pads include a metal wear indicator that produces a warning sound when the pad becomes too thin. This warning may be heard while the vehicle is moving and the brakes are not being applied.