Why It’s Essential To Maintain Your Car’s Brake Fluid Level

When you fill up your car with fuel and check your oil and water, do you also check your brake fluid regularly? Probably not, but you should because it’s essential for the safe operation of your car. If your brake fluid level is too low, or the fluid contains contaminants or too much water, your brakes won’t work as well as they should.

Here’s a quick recap on how brake fluid works. Hydraulic brake and clutch systems found in modern cars require hydraulic (brake) fluid in order to work. When you push the brake pedal, the power from your foot is transferred to the brakes pads at the front and back of your car through brake fluid, which is incompressible. This force is then transferred from the brake pads to the wheel and friction causes your car to slow or stop. Insufficient or diluted brake fluid limits this force and your ability to slow down or stop your car.

It’s easy to see the importance of brake fluid, but it’s also essential to understand the factors that can impact its quality and levels, putting your safety at risk.

Checking your brake fluid regularly will enable you to do more than just check the level; if you know what to look for, you can spot a potential problem early and take action.


If the level has dropped just a little, simply top it up as this is normal. But if the level is constantly dropping, you may have a leak, which you need to have repaired immediately. If your brake fluid is leaking, the resulting loss of hydraulic pressure will have a significant impact on your ability to brake or slow your vehicle.

As your brake pads wear down, your brake pad fluid level will fall, so if you’re regularly topping up, it may be time to change your brake pads.


Brake fluid used by today’s vehicles are glycol-ether based, and due to their chemical structure, they absorb atmospheric moisture through exposure to the air and via microscopic pores in hoses and worn seals. This absorption process happens continuously, and the problem lies in how this moisture affects the fluidity – or viscosity – of the brake fluid. Consistent viscosity – even in extreme temperatures is essential for the brake fluid to work correctly, particularly if your car has traction and stability control and an anti-lock braking system (ABS). If the fluid is too thick or thin, the consequences could be devastating.


Brake fluid protects a number of metal parts in your vehicle, including the wheel cylinders, ABS and callipers from corrosion caused by the moisture entering the system. For this reason, almost all brake fluids contain some form of corrosion inhibitor, but this chemical has a limited lifespan. Corrosion damage can be very costly, so it pays to flush and replace your brake fluid regularly.

No-one can afford to compromise on braking capacity, so don’t neglect this vital part of vehicle maintenance. Get into the habit of checking your brake fluid levels monthly. The team at Midas will be able to show you how to check and change your brake fluid. Contact us today.