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What is a brake fluid flush?

Car mechanic bleed air out of brake system

Brakes are the safety features that keep you out of harm’s way, and they rely on the brake fluid to stop or slow down your car when you need to. Contaminated brake fluid causes brake failure until the component is changed and the brake fluid is flushed. But you don’t have to let it get that far!

What is a Brake Fluid Flush?

When changing brake calipers, rotors, and pads, we recommend that you also flush out the brake fluid to remove dirty fluid inside the brake lines, especially on cars with anti-lock brakes and traction control to enhance efficiency. When you replace the fluid containing water and contaminants with new fluid, it makes the car’s braking system more effective.

A professional mechanic should replace brake fluid every time you install a set of new pads, usually after every 35-60k miles. Performing a brake fluid flush improves your car’s overall performance and reduces the risk of brake or wheel cylinder failure.

How to Perform a Brake Fluid Flush

Just like changing oil, flushing the brake fluid is an easy task. Two people perform the fluid flush, where one operates the pedal and holds while the other opens the bleeder screw for under 2 seconds. You will also require a quart of DOT 3 or Dot 4 fluid of your favorite brand of brake fluid.

If you have never performed this task, we advise that you have a professional handle the process of flushing and replacing your brake fluid.

  • Step 1: Empty the Master Cylinder Reservoir

Using a large syringe, a small siphon pump, turkey baster, or transfer pump and tube, remove all the brake fluid inside the reservoir while the car is off and parked. Also, ensure there’s no pressure on the brakes.

  • Step 2: Fill and Bleed

Fill the master cylinder reservoir with new fluid. Fit a 2-foot section of clear tubing over the bleeder screw to observe as all the old fluid drains out. Starting with the two rear wheel cylinders, ensure that all the rusty, brown fluid flows out and clear oil flows through the tube. Afterward, proceed to fill and bleed the front wheels.

  • Step 3: Top it off

After draining the last wheel, fill the cylinder reservoir back to the fill line. Ensure that you flush your brake fluid every three years or 30,000 miles.

Why you should flush your Brake Fluid on Time

  1. Brake fluid is hygroscopic so that it readily absorbs moisture from the air. Since the braking system has metallic components, flushing prevents corrosion and failure of these components.
  2. Contaminated fluid has a lower boiling point and does not perform optimally.
  3. The antilock braking system (ABS) and traction control activate and generate heat, breaking down the brake fluid further, and shortening the lifespan of your brake fluid.
  4. Moisture and particulates in the contaminated fluid reduce the efficiency of the ABS and traction control.

If you need a brake fluid flush performed, we invite you to bring your vehicle to John’s Auto Care today!