What is the main purpose of brake fluid?

The main purpose of brake fluid is to transmit force and ensure proper brake function. When the driver presses the brake pedal, this action creates pressure in the brake fluid, which travels through the brake lines to the brake components. This hydraulic force activates the brakes, causing the brake pads to clamp down on the rotors, resulting in deceleration or stopping of the vehicle. The effectiveness of the brake system relies heavily on the integrity and functionality of the brake fluid, making it essential for safe driving.

While cooling the brakes is important, it is not the primary function of brake fluid itself. The brake system is designed to manage heat through various means, including the brake pads and rotors, rather than relying solely on the fluid. Similarly, lubricating the brake pads is not a function of brake fluid; instead, separate lubricants or specialized materials are used for this purpose. Lastly, while preventing rust in the brake lines is valuable for system longevity and performance, it is not the main purpose of brake fluid, which is fundamentally a hydraulic medium for force transmission.