Brake Fluid
- Brake fluid must never come into contact with fluids containing mineral oils (oil, gas, cleaning solutions). Mineral oil damages the plugs and rubber grommets in the brake system.
- Brake fluid is poisonous. NEVER siphon brake fluid with your mouth! Also due to its corrosive effect, brake fluid must not come into contact with paintwork.
- Brake fluid is hygroscopic, meaning that it absorbs moisture from the surrounding air, and must therefore be stored in air-tight containers.
- When bleeding, brake fluid that has been flushed through must not be reused and must be disposed of properly.
- Observe waste disposal regulations!
Only use new brake fluid conforming to US-Norm FMVSS 116 DOT 4.
Genuine VW/Audi brake fluid conforms to this specification.
Do not use any silicone-based fluid.
Avoid contaminating brake fluid with particles or lint (for example from cleaning cloths).
Wash off any spilled brake fluid with plenty of water.
If system is open, do not work with compressed air and do not move the vehicle.
During final road test, carry out at least one ABS-controlled braking operation (appropriate pulsations must be felt at brake pedal).
Brake fluid is hygroscopic, i.e. it has the capability 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 specify anything about its quality. The coloring occurs through chemical reactions and can occur after a short time (several weeks), especially in vehicles with ABS.
The rubber components of the brake system (rubber grommets, seals) do not tolerate mineral oil, gasoline, and cleaning agents!
Even the smallest amount on a seal or rubber grommet 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 = rubber grommet - original size
B = Rubber grommet - swollen through contact with mineral oil
It is implied by the previously mentioned points that:
Keep containers of brake fluid closed securely. This is to make sure that no oil, dirt or cleaning materials and no humidity can enter the container.
Store containers of brake fluid 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.