How to top up brake fluid

Brake fluid is essential for a functioning braking system in your car. Without brake fluid, your brakes would cease to function. Therefore, it is your responsibility to check and top up the brake fluid for your vehicle. Discover how to tell when your brake fluid is low, how to top up brake fluid and how to check your brake fluid levels in our guide.

Firstly, how does brake fluid work?

Brake fluid is a crucial part of your car’s braking system. Brake fluid, which is also known as hydraulic fluid, cannot be compressed so when pressure is applied to the brake pedal the fluid becomes pressurized and is forced through the braking system and compresses the brake pads to effectively stop the vehicle. Brake fluid will also prevent corrosion and keep the braking system lubricated. 

What are the signs of low brake fluid?

Having the right amount of brake fluid is necessary for your braking system. You may notice the following signs if you have low brake fluid, such as:

• A stiff brake pedal – If your car has low brake fluid, you may have difficulty applying the brake pedal.
• Unnecessary ABS – When driving, if you notice the anti-lock braking system kicks in on a non-slippery surface, it’s a sign to check your brake fluid.
• Vibrations when braking – Have you noticed a vibrating sound while applying your car’s brakes? It could be a sign of low brake fluid.
• Loud and squeaky brakes – Your car’s brakes are not meant to squeak. If your car screeches or squeaks while braking, it could mean low brake fluid.

How to check brake fluid

If you notice any of the above symptoms while driving, it is time to check your brake fluid level. Our simple steps will help you to establish how to top your brake fluid up:

1. Drive your vehicle for a few minutes to fill the braking system with fluid.
2. Once you’ve parked your car and turned off the engine, open the bonnet and locate the brake fluid reservoir. If you are unsure where this is, check the owner’s manual.
3. Look for where the fluid lies – it should be within 2cm of the top of the cap and in line with the maximum and minimum markers.
4. Check the colour of your brake fluid. It should be white. If the fluid is dark-coloured, it should be replaced.

Topping up brake fluid

If you notice that the brake fluid is not within the minimum or maximum level for your car, or is dark in colour, it must be topped up or replaced. Over time, your brake fluid will deteriorate with regular use. If your brake fluid is low or needs replacing, you can either have it replaced by a professional or replace it yourself by following our four simple steps:

1. Open the reservoir cap
2. Slowly add the brake fluid to the reservoir, using a funnel until it meets the maximum marker.
3. Close the reservoir cap, ensuring it is screwed on tightly.
4. Drive your car to check that the brakes are working.

Topping your vehicle’s braking system with the correct fluid is crucial for the brakes to function. Discover how your car’s brakes work and the signs of brake failure from our dedicated brakes page. Book your free brake check at your nearest Merityre garage across South East England today.