How to Flush and Replace Brake Fluid

Brake fluid isn’t something the average person thinks about too often. The average car owner will check his brake fluid levels when he checks his other fluids but he doesn’t think about it much after that. Believe it or not, you should replace brake fluid on a regular basis in addition to regular auto repair and maintenance.

Why You Need to Flush Your Brake Fluid

Brake Fluid

Brake fluid is a hygroscopic liquid, meaning it likes to absorb water. It loves water so much it will even pull moisture out of the air. The problem is that water and your brakes don’t actually get along. The water makes it difficult for your brake fluid to reach a boiling point, which means it won’t work as effectively. The extra moisture can also cause the fluid to corrode the expensive pieces that make up your braking system.

Flushing Your Brake Fluid

The process of flushing brake fluid from your vehicle isn’t very difficult. The task is usually a two-person job.

Start by taking your vehicle on a quick road test, applying the brakes normally so you can gauge how they feel. Once you’ve returned to your starting point you will want to make sure the car is parked on a flat and level surface before setting the parking brake.

Open your vehicle’s hood, locate the brake fluid reservoir for the master cylinder, drain it completely, and refill it and replace brake fluid.

The next step is to loosen the lug nuts on your tires. Loosen them slightly but don’t remove the nuts completely. Use a car jack to raise your vehicle from the ground and secure it with a set of jack stands at each corner. Once the vehicle is raised you can complete the removal of the lug nuts and the wheels.

You’re going to start by locating the brake bleeder valve for the rear wheel on the passenger side of your car. Slide a piece of clear plastic tubing so that it completely covers the bleeder valve and place the opposite end into a clear plastic container. The container should have about 2 inches of brake fluid in it already.

Here’s where your assistant comes into play. Have the person helping you place a small block of wood, about an inch thick, under the brake pedal so that it can’t be pushed all the way to the floor. Your helper will pump the pedal a few times and then hold it down. While he is holding the pedal down, you will crack your vehicle’s bleeder valve. You’ll see old, dirty brake fluid entering the container. Re-tighten the valve when the fluid and air bubbles stop running.  Repeat the process of pumping the brake, opening the valve, and closing the valve until you see new, clean brake fluid entering the container.

Repeat this process for the other 3 wheels, moving around to the driver’s side rear, back to the passenger side front, and over to the driver side front wheel. Once you’re finished you can reinstall the wheels and lower your vehicle back to the ground, making sure the lug nuts are snug. Take your car for another test drive to make sure the brakes are working properly.

While this may be a relatively easy task for those who are mechanically inclined, not everyone will feel comfortable doing this sort of work. Never attempt to perform any type of maintenance on your car if you are not sure of the process. Contact your favorite auto mechanic for help instead.

About the author

Travis Whiteside By Travis Whiteside, owner of Everest Auto Repair in Newark DE after coming up in the ranks as the lead ASE Certified Mechanic. We believe in providing hassle free auto repairs and dealer approved maintenance while keeping it as affordable as possible to you. Book an appointment today 302-737-8424. Connect with Travis on Google+