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4.1 Brake Fluid

Brake fluid is the heart of the brakes' hydraulic system. It transmits the mechanical braking force at the pedal to the brake mechanisms at the wheels. Any contamination of the fluid will have a direct influence on braking efficiency. Dirt in the system will clog small passages and damage rubber parts.

Brake fluid absorbs moisture. Moisture in the fluid lowers its boiling point, allowing it to be boiled more easily by the heat generated during braking. Boiling the fluid will create air bubbles in the system and, since air is compressible, will reduce braking efficiency. Moisture in the system also causes corrosion.

When adding brake fluid, use only new fluid from unopened containers. Do not reuse brake fluid that has been bled from the system, even if it is brand new. The bleeding operation aerates the fluid. See LUBRICATION AND MAINTENANCE for brake fluid specifications. For best performance and system reliability, use only Volkswagen-approved brake fluid.

Because it readily absorbs moisture, brake fluid should be changed every two years, regardless of the number of miles driven annually. See Replacing Brake Fluid for more information. The brake system should also be bled of air after any repairs in which brake lines are disconnected.

WARNING-

Brake fluid is poisonous. Wear safety glasses when working with brake fluid, and wear rubber gloves to prevent brake fluid from entering the bloodstream through cuts or scratches. Do not siphon brake fluid by mouth.

CAUTION-
Brake fluid absorbs moisture from the air. Add only unused fluid to the system, and only from well-sealed or previously unopened containers.

Do not use silicone-based (DOT 5) brake fluid. Even the smallest amount may cause severe corrosion in the brake hydraulic system.

Brake fluid is very damaging to paint and rubber parts. Immediately wipe up any brake fluid that spills on the vehicle.

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