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General Information, Brake Fluid

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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.

GWWN47-0016Courtesy of AUDI OF AMERICA, LLC

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.

A = Boot - Original size

GWWN47-0013Courtesy of AUDI OF AMERICA, LLC

B = Boot - Swollen through contact with mineral oil

As a result of the previously mentioned points:

WARNING:

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 :5Q0698311  .
  • 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.
NOTE:

Use new brake fluid only.

Rinse any spilled brake fluid with plenty of water.