How does brake fluid work?

Bradley Jando | Monday 2nd August 2021 5:01pm

Technician pouring brake fluid

As a crucial part of your car’s functionality, brakes are typically at the top of the priority list when it comes to checking that the various elements of your car are working the way that they should.

There are multiple components of your car’s brakes that need to be working together to keep things running smoothly. That said, here are some components that we’ve heard more about than others - such as the brake pedal, brake lines, brake discs and brake pads.

Brake fluid, also known as hydraulic fluid, is an essential aspect of your brakes. It not only amplifies your car’s braking force but it also acts as a lubricant and prevents corrosion in moving parts of your brakes. Simply put, without brake fluid, your brakes wouldn’t work. You can find out more about why brake fluid is important here.

The braking system

So, as such an important part of your brake system, how does brake fluid work?

Brake fluid is part of the braking process from the moment you put your foot down to brake. When you press down on your brake pedal, the pistons inside the master cylinder, which lives within the engine compartment, compress to allow the brake fluid to travel under pressure. The compression from the pistons increases the pressure within the brake lines which is where the pressurised brake fluid is contained.

The brake lines divert the force of you pushing down on the brake pedal into the front and rear brakes of your car using the pressurised brake fluid. The brake fluid then converts the energy used to push down the brake pedal into braking pressure that causes the brake pads to squeeze the brake rotors. This leads the rotors to slow down and brings them to a halt.

Looking to learn a bit more about your car’s brakes outside of the brake fluid? We have plenty of information available for you to get to grips with on our brake information page.

Keeping your brake fluid at its best

Your brake fluid is best when it is fresh and uncontaminated, as this means your brake system is working properly and brakes efficiently when you put your foot down on the brake pedal.

As the brake fluid also acts as a lubricant to other moving parts of your braking system, it can absorb any moisture that might come from those components. Because of the elements of the car that the brake fluid comes into contact with when you brake, it is subjected to high temperatures.

The more water that enters your brake fluid, the further diluted it becomes. This then lowers the temperature at which the fluid boils - at which can result in your brakes failing to stop your car. By ensuring that your fluid’s boiling point is checked, you can keep your brake fluid at its best and prevent any braking accidents that could occur.

Kwik Fit Brake Service

Here at Kwik Fit, we offer a variety of checks and services for your car to ensure that it performs at its best, including a new brake fluid change service - to keep your brakes working at their best, and potentially prevent the additional cost of a premature brake replacement.

To book your car in, get in touch by visiting your local Kwik Fit centre.

Any facts, figures and prices shown in our blog articles are correct at time of publication.

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