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Why change brake fluid

Changing your brake fluid is essential to your car’s performance, learn how often to change your brake fluid with Castrol's car maintenance guide.

Brake Fluid Change

Brake fluid change 

 

Brakes are essential for any car and this makes brake fluid one of your car's most important components. Brake fluids resist the moisture that can cause vapour lock brake failure, protect against corrosion, and withstand high brake temperatures. That’s why you should ask yourself the question “how often should brake fluid be changed?”. 

 

How often should you change brake fluid?

 

There is no single answer to how often to change brake fluid as it depends upon how the car has been driven and can vary by make and model. Most manufacturers recommend changing brake fluid at least every two years.

 

Because it plays a crucial role in keeping you safe and because it’s not easy to tell how often you should change brake fluid, it is advisable to carry out a visual inspection of the fluid much more frequently. There are four tell tale signs that a brake fluid might need to be changed.

 

  1. If the fluid is dirty. Brake fluids should be clear in appearance
  2. If the fluid smells burnt
  3. If the brake pedal feels spongy
  4. If the level of fluid in the reservoir has dropped

 

Why is brake fluid important?

 

Modern engines work at high pressure and place heavy demands upon braking systems. When we think about brakes we typically think about discs and pads and expect them to experience wear and tear. Important though discs and pads are, they are part of an hydraulic system that relies upon a brake fluid to function and will not work without a brake fluid. A healthy brake fluid is therefore essential.

 

Brake fluids like to suck up moisture and this is bad news. Moisture reduces the boiling point of the fluid. When a brake fluid boils, it becomes compressed and unresponsive to pressure upon the brake pedal. You may even have experienced a diminution of brake performance after a period of heavy braking such as the descent of a steep hill. It is therefore important that you use a high quality brake fluid such as Castrol React Performance Dot 4. Your vehicle handbook will tell you how often you should change brake fluid.

 

What is included in a brake fluid change?

A mechanic will follow the following steps in changing your brake fluid:

  1. Draining down the old fluid
  2. Changing the fluid
  3. Flushing the calipers and wheel cylinders
  4. Bleeding the brakes
  5. Topping up with new fluid
  6. Repeating the process


Read more on how to change your brake fluid


Castrol React Performance DOT 4 brake fluid


Castrol Dot 4 brake fluid  is liquid engineered to prevent vapour lock and protect your brake system.