Brake Master Cylinder 8D0611021BX

Image is an example only, BRAND MAY VARY

A brake master cylinder is one of the most crucial components in a car's brake system. It works by converting the force from the brake pedal into hydraulic pressure that pushes the brake fluid into the brake lines, which in turn triggers the brake calipers or wheel cylinders to clamp down on the brake pads or shoes and slow down or stop the wheels' motion. The brake master cylinder usually consists of a cylinder, a piston, and a reservoir that stores brake fluid.

When the driver steps on the brake pedal, a pushrod or booster mechanism will apply pressure to the piston inside the brake master cylinder, causing it to move forward and apply pressure to the brake fluid. The brake fluid will then travel through the brake lines and apply pressure to the brakes, either through a hydraulic disc or drum brake system. A defective brake master cylinder could cause various brake-related problems, from spongy brake pedal feel to a total brake failure, making it essential to check and replace the brake master cylinder regularly as part of the car's maintenance.