What is Brake fluid and Why is it Important?

break fluid

What is Brake fluid and Why is it Important?

Brake fluid is a type of hydraulic fluid used in hydraulic brake and hydraulic clutch applications in vehicles. It undeniably plays a key role in your braking system as it performs the function of transferring the force created when a driver presses the brake pedal directly onto the wheel hub.


Brake fluid is hygroscopic which essentially means that it takes in moisture during the course of its life in your vehicle through the pipes and joints that it lubricates. As the water quantity in the brake fluid rises, the temperature the liquid boils at gradually decreases. The boiling point can be heavily reduced by water contamination which will have an adverse effect on your braking ability. 


Additionally, brake fluid is affected because of several factors such as age of the brake fluid, the level of corrosion inhibitors, and environmental and driving habits all basically contribute to when your brake fluid will need to be replaced.


As mentioned earlier, brake fluid has hygroscopic properties so moisture is naturally pulled into the fluid through the atmosphere. Moisture contamination can significantly lower your brake fluid’s boiling point, therefore making it highly likely to overheat and gradually lose its effectiveness. Listed below are some of the signs that your brake fluid is contaminated:


  • You need to start braking way earlier than you used to
  • Your dashboard has a warning light 
  • Your brake pedal needs excessive pressure to respond
  • Your brake pedal responds more slowly


If you notice any of the above signs, it’s wise to have your vehicle checked by a professional mobile car mechanic


Brake fluid is vital to the safe operation of your vehicle. Routinely inspecting your vehicle’s brake fluid levels, should be one of your top priorities. It should be checked on a weekly basis, at the very least, a fortnightly basis without fail. Driving a vehicle with diminishing brake fluid compromises the safety of you, your passengers on board, and also other drivers on the road. It’s highly advised to have a mobile car mechanic examine your brake fluid.