How Do You Flush Brake Fluid?

Flush brake fluid from a car by emptying the reservoir, filling it with fresh fluid and bleeding the brakes until clear fluid exits the lines. Only use the brake fluid your vehicle manufacturer specifies.

  1. Empty the master cylinder reservoir

    Wipe the master cylinder reservoir clean of all debris before opening the cap. Use a large syringe or turkey baster to remove as much of the liquid as possible from the reservoir. If the reservoir has a large enough opening, use a lint-free rag to wipe the interior.

  2. Fill the reservoir with new brake fluid

    Use a new container of brake fluid to fill the reservoir to the maximum fill line. To avoid damaging the brake system, don't use brake fluid from open cans.

  3. Bleed the brakes

    Attach a clear plastic tube to the bleeder valve farthest from the master cylinder. Have an assistant press and hold the brake pedal. Open each valve to allow the old oil to escape, and tighten the valve each time the assistant presses the pedal. Continue to open and tighten the valves until clear liquid escapes the tube without bubbles. Repeat the process for each wheel on the car, making sure the fluid in the master cylinder remains above the minimum line.