Brake Fluid General Information
Brake fluid is hygroscopic, meaning that it has the ability to absorb water and moisture from the air.
If water has been absorbed, the boiling point will drop, for example, during high braking temperatures the brake fluid may develop steam bubbles and cause the brakes to fail.
Over time, brake fluid will darken in color. Dark-colored brake fluid does not indicate anything about its quality. The color forms due to chemical reactions.
Even the smallest amount on a seal or boot can cause the part to change and thereby affect the function of the brake system. The results of an unclean brake system first show themselves months later, causing increased repair costs, especially on vehicles with ABS.
Courtesy of AUDI OF AMERICA, LLCA -
Boot - Original size
B -
Boot - Swollen through contact with mineral oil
As a result of the previously mentioned points:
- Keep brake fluid containers tightly and securely sealed. Only this can ensure that no oil, dirt or cleaning materials and no humidity can enter the container.
- Store brake fluid containers away from oil (even hydraulic oil) and cleaning fluids to prevent an accidental mixing of both fluids or even filling the brake system with the wrong fluid.
Health risks!
- Brake fluid is poisonous, and must never be siphoned by mouth under any circumstances.
- To prevent skin contact with brake fluid, wear chemical resistant safety gloves.
- Follow all disposal regulations.
There is a risk of an accident from steam bubbles developing when the water content in the brake fluid is too high.
- Brake fluid is hygroscopic, meaning that it absorbs moisture from the surrounding air.
- Seal the open brake hoses and brake line with plugs from the Assembly Part Set :5Q0 698 311 .
- Always store brake fluid in air-tight containers.
Brake fluid contact with fluids containing mineral oils causes malfunctions.
- Brake fluid must never come into contact with fluids containing mineral oils (oil, gas, cleaning solutions). Safety gloves must be free of oil and grease.
Risk of damaging the painted surfaces.
- Due to its corrosive nature, brake fluid must also never contact paint. Wash off any spilled brake fluid immediately with plenty of water.
Only use new brake fluid.