Purpose and Specifications

ATE DOT 4 Brake Fluid (03.9901-6403.2) is a premium 5-liter can of high-performance hydraulic fluid designed for reliable braking in cars, trucks, and motorcycles. This glycol-based fluid absorbs moisture faster than DOT 3 but delivers superior heat resistance with a dry boiling point over 230°C and wet boiling point above 155°C, preventing brake fade during heavy towing, mountain driving, or spirited street use.

It lubricates moving parts, protects metal components like cast iron, steel, and aluminum from corrosion, and ensures crisp ABS and ESP response even in cold weather down to -40°C. Backward compatible with DOT 3 systems (unless OEM specifies otherwise), it mixes seamlessly for easy upgrades while maintaining stable performance over time.

• 5-liter container for full system flushes or shop use
• Premium ATE quality trusted by mechanics worldwide
• High thermal stability keeps brakes effective under extreme loads

When to Use / Replace?

Use ATE DOT 4 for daily drivers with ABS/ESP, performance vehicles, or any setup demanding better heat tolerance than DOT 3. Ideal for towing trailers, hilly roads, or fast highway runs where brakes heat up quickly.

Replace every 2 years or 40,000 km, or sooner if pedal feels spongy, as it naturally absorbs water over time, dropping its boiling point and risking vapor lock. Unopened shelf life is 3-5 years in a cool, dry place.

FAQ

Q: Can I mix this with my existing DOT 3 fluid?
A: Yes, fully compatible for topping off or flushing without issues.

Q: Is it safe for cold climates?
A: Absolutely, flows smoothly at -40°C for reliable ABS activation in winter.

Q: How do I know when to flush my brakes?
A: Check every 2 years/40,000 km; flush if fluid looks dark or contaminated.