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11 Brake Fluid Service FAQ

For those readers who may be unfamiliar with brake fluid servicing, the following are some frequently asked questions:

Macs Radiator FAQs about Brake fluid



How does brake fluid work?


Brake fluid works like hydraulic fluid. It’s pumped from the master cylinder to the wheel cylinders and calipers through hoses. When the brake pedal is pressed, the fluid pushes the brake pistons into the brake pads, which applies the brakes to the wheels. When the brake pedal is released, the fluid is pushed back into the master cylinder.



What is brake fluid made of?


The fluid is a hydraulic fluid that is primarily made of propylene glycol dinitrate (PGDN). PGDN is a non-corrosive, non-toxic, petroleum-based, polyhydric alcohol. It’s a colorless liquid with a sweet odor.



Why should I get my brake fluid serviced?


Brake fluid absorbs moisture from the air, which causes the fluid to break down and has an adverse effect on the performance of the brake system. This can cause increased stopping distance, which is critical in an emergency or crash situation. Brake fluid that’s been serviced over time will also be better protected against corrosion.



Does my brake fluid need to be changed if my brakes are working fine?


Yes. Brake fluid is hygroscopic, meaning that it absorbs moisture from the air. This water content is corrosive to metal components. Water will cause the brake fluid to boil at a lower temperature. This can cause the brakes to fail, which is why we recommend any leaks be fixed immediately.



How do I know if my brake fluid is bad?


The brake fluid will turn a rust color and will smell like burned oil. If the fluid is a dark red color, it indicates that the fluid is old and is due for replacement.



When should I get my brake fluid replaced?


Your brake fluid will be a red-amber color. If your brake fluid has this color or has a strong odor, it’s time to have the fluid replaced. If you’re having problems with your brakes or have any of the below symptoms, have your brake fluid replaced immediately:

  • Brake fluid is dirty or rusty
  • Brake fluid is leaking or seeping
  • Brake pedal is sinking
  • Brake pedal is spongy
  • Brake pedal is stiff
  • The vehicle pulls to one side



How often should my brake fluid be serviced?


Brake fluid is a closed system, which means that it shouldn’t be serviced until it’s contaminated. Brake fluid can be contaminated when the brake hoses are exposed to dirt or the brake fluid is exposed to moisture.

The frequency of the brake fluid service will depend on the amount of driving you do, the weather conditions you are driving in, and how well the vehicle is maintained. Brake fluid service intervals can be different for different models of vehicles, but generally, brake fluid should be replaced every 2 years or 24,000 miles.



What does brake fluid service include?


Our professional service technicians will change the brake fluid, inspect the system for leaks, and check the condition of the hoses and hardware.



What should I look for when I get my brake fluid serviced?


You should look for any signs of leakage on the brake calipers, master cylinder, or lines. Any leaks or drips are a sign that there may be a problem with the system and should be addressed immediately.



What should I do if my brakes squeal or my brake pedal is low or spongy?


If your brakes are squealing or you’re noticing a low or spongy brake pedal, have us inspect your vehicle. If there’s any corrosion, we’ll flush and replace the brake fluid and bleed your brake system.



Is brake fluid flammable?


Yes. If brake fluid comes into contact with a hot surface, such as hot brake calipers, it will ignite and burn. For this reason, it is extremely important to keep brake fluid away from any kind of heating device.


Macs Radiator FAQs about Brake fluid mechanic does a brake fluid check up




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Portland, OR      (503) 777-4706
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