Q: How does brake fluid get dirty?

asked by on

How does brake fluid get dirty?

One way that brake fluid becomes contaminated is when moisture is absorbed by the brake fluid through rubber brake lines. This moisture will break down the brake fluid and cause rust in the brake system. Excess moisture in brake fluid will increase its temperature because the boiling point of water is lower than that of brake fluid. When this happens air gets into the brake lines and the brakes may become less effective. Brake fluid that has been contaminated by water or moisture can also weaken the master cylinder and caliper rubber seals and lead to brake leaks and an overall failure of the brake system. This type of contamination most commonly occurs in an environment that is particularly humid and in conditions of heavy braking. Another way that brake fluid becomes contaminated is when grime and debris from the brake system accumulates in the brake fluid. Over time, the heat that is generated from braking causes the brake fluid to break down and become contaminated. Brake fluid should normally be changed every two years but this is something that may already be included in the maintenance schedule for your vehicle. Pay close attention to the color of your brake fluid. Normal brake fluid should be a light yellow color and look almost clear, while contaminated brake fluid looks dark brown or black in color.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. How does brake fluid get dirty?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Q: Grinding noise when braking

You should have your brakes inspected for any issues like metal to metal grinding or another related issue. This may just be a brake pad service issue or a more serious problem with the ESC. Only a thorough check will...

Q: Car leaking fluid.

A fluid leak from somewhere on your vehicle could be something normal like water condensation from your AC. Identifying an approximate location of the leak, and the type of fluid, would help in a diagnosis of your leak. A black...

Q: Q: No brake pressure.

Hi, no pressure on your brake pedal usually means one of two things. If you have had any work done on your brakes, it is possible that there is some air in your hydraulic lines. The air simply has to...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...