How to change brake fluid easily

change brake fluid easily

How do you change brake fluid easily? Our guide takes you through it step by step and explains why — and how often — you should do it.

The brake fluid is an important component for driving safety. It transfers the power of the brake pedal to the wheel. This slows down the car when you step on the brake.

The heat generated by the friction can decompose or evaporate the brake fluid over time. Then the brakes will no longer work properly, which can be very dangerous not only when driving at high speed or in high-traffic areas.

The brake fluid also has another purpose. It serves as a lubricant for moving parts and prevents rusting or caking. When your brake fluid is no longer in good condition, various parts of the car can be affected. Over time, the brake fluid can absorb water through small holes in the seals and lines. Water changes the properties of the brake fluid negatively. Therefore, it is extremely important to change the brake fluid regularly to ensure that your car is working safely.

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Steps to change brake fluid easily

The brake fluid should be changed every two years. At longer intervals it is likely that the water content in it will become too high.

  1. Before you change the brake fluid, you must drain the system. For this you need a container that catches the old liquid, a wrench and a can of brake cleaner.
  2. First clean the container with the brake cleaner spray before opening it. (Caution: brake cleaner is usually very easy to ignite!)
  3. The next step is to drain the old fluid. You can either work with negative pressure or with positive pressure. In both cases you need a suitable device for this.
  4. When you have removed the old brake fluid, you need to fill the cylinder with the new fluid. Make sure you have bought the right brake fluid for your car. This is classified according to the boiling point. Most cars have DOT 4 or DOT 5.1 brake fluids. Please check in advance which one you need.
    After that you have to lift the car slightly. A jack is all it takes. So you can get to each brake individually. Someone has to help you with this step by pressing the brake slightly. When the pedal is depressed, the valves on each wheel open and allow the old brake fluid to drain into the reservoir. As soon as your assistant has pressed the pedal all the way to the floor, you should close the valve again so that unnecessary moisture cannot penetrate the system.
    Repeat this step for each wheel until the liquid is clear. You may need to refill the main container several times.
  5. When you’ve done this for each wheel, pump the brake pedal 20 or 30 times to increase the amount of fluid in the main reservoir.
  6. If the brake light comes on after you have completed the process, pressing the brake pedal quickly and firmly should extinguish the light.

Why is it important to change the brake fluid regularly?

In order for the brake fluid to do its job properly, it is important that it is not contaminated with other substances. Water or air in the liquid degrade the performance of the car. Neither water nor air can withstand the high pressure as well as the brake fluid.

Ways to drain the brake fluid

There are several methods you can use to drain the old brake fluid. Using overpressure is probably the easiest method. You can buy the necessary device for little money and save yourself a lot of trouble when draining.
The vacuum method is just as effective, but it is more expensive because you need a good vacuum pump to do it. In addition, it must also fit on the vent valve so that the liquid runs off and no water and no air penetrate.

Easy to do, but time consuming and dirty

Changing the brake fluid is not particularly difficult. However, you have to expect that it will take a long time and be quite dirty. The tools you need to do this can be expensive, even if the liquid doesn’t cost much. If you like to get your hands (and probably your clothes too) dirty, you can save money. However, your workshop already has all the tools and the knowledge to make the change and you will save a lot of time that you can use more sensibly.