How Does Brake Fluid Work?

Brake Fluid Circulates and is Pressurized

Automotive brake fluid supplies the force necessary to activate the stopping mechanisms of a car's brake system. Brake fluid, which circulates through a series of metal lines and tubes, is pressurized by the brake booster each time the brake pedal is pushed.

Brake Fluid Makes Stopping Possible

Brake shoes supply the necessary friction to stop a car's wheels from spinning. Brake fluid under pressure is what supplies the force necessary to squeeze the brake shoes against the rotating insides of a car's tires. A mechanical braking system in contrast, as used on bicycles, uses cables to squeeze the brake shoes against the tires; hydraulic braking systems use brake fluid to operate the brake shoes.

Brake Fluid Storage

When a car is not running or when the brake system is not being utilized, brake fluid resides in a special rectangular compartment located in the engine compartment called the master cylinder. The master cylinder has a series of metal tubes attached to it that serve as an entry and exit point for circulating brake fluid.