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How to Top Up Brake Fluid

Bradley Jando | Monday 5th July 2021 3:17pm

Brake fluid under bonnet

Brake fluid is an essential part of your car’s braking system; if the levels are too low, your brakes’ effectiveness will reduce or cease to function altogether.

When you press the brake pedal, hydraulic fluid is pushed down to activate your brake pads. As well as keeping your brakes functioning, brake fluid is also a lubricant with anti-corrosive properties, so it helps keep your braking system healthy overall.

If you’ve never topped up your brake fluid before, it can feel like an alien task - but luckily, it’s actually fairly easy to do.

1. Locate your master cylinder

You can find this by reading your vehicle handbook. It’ll usually be located under the bonnet, on the driver’s side of the vehicle – towards the back of the engine compartment.

You’ll see a metal cylinder with a plastic container on top - this is the brake fluid reservoir.

In most cases, the cap itself will indicate you’re in the right place, inscribed with ‘brake fluid’.

There’ll be a full line and a minimum line, and in modern cars, you should be able to see the fluid level from the outside. Hot tip: if you’re not parked on a flat surface, your reading probably won’t be accurate!

2. Make sure you buy the right brake fluid for your car

The cap of the brake fluid reservoir will usually tell you what kind of brake fluid you should use - DOT3, DOT4, or DOT5.

If you can’t find it here, you can also look it up in your vehicle handbook.

3. Pour in the brake fluid

This is the easiest part! Simply open the cap and pour in the brake fluid until it reaches the ‘maximum’ line. Screw the cap back on securely, shut your bonnet, and you’re ready to go (or stop!).

Maintaining brake fluid levels

Seeing as brake fluid is such a vital component within your braking system, you should ideally check the levels every week.

If you notice that the levels get low again pretty soon, you might have a leak - and you should book an appointment at your local garage as soon as you can.

Brake fluid can deteriorate over time and absorb water content, which makes it much less effective. Most manufacturers recommend changing out your brake fluid altogether every 2 years. This part is a job for a mechanic!

Kwik Fit has you covered with our brake fluid change service, and when you book online, you also get a free comprehensive brake check to keep you and your vehicle safe.

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