Motul RBF 660 Factory Line is a 100% synthetic DOT 4 racing brake fluid engineered for hydraulically actuated brake and clutch systems exposed to extreme operating temperatures.

With a dry boiling point of 325°C / 617°F and a wet boiling point of 205°C / 401°F, it provides strong resistance to vapor lock and brake-pedal fade during racing, track-day, performance street, and other high-temperature braking conditions.

It is suitable for carbon, ceramic, and conventional steel braking systems, as well as compatible hydraulic clutch actuators requiring a non-silicone synthetic brake fluid.

WHY THIS BRAKE FLUID:

The extremely high 325°C dry boiling point helps maintain consistent hydraulic pressure during severe braking where conventional brake fluids may begin to boil.

The high 205°C wet boiling point supports reliable braking performance after the fluid has absorbed moisture through normal service use.

Its performance-oriented formulation helps reduce the risk of vapor lock, brake fade, a soft pedal, and inconsistent braking response under repeated high-temperature braking.

The fluid is suitable for conventional hydraulic clutch systems and performance braking systems using compatible seals and materials.

It meets FMVSS 116 DOT 4 and SAE J1703 / J1704 standards. It also exceeds the boiling-point requirements of DOT 3 and non-silicone DOT 5.1 fluids, but does not meet the DOT 5.1 viscosity requirement at minus 40°C.

BEST FOR:

Racing and track-day brake systems

Performance street vehicles

Carbon, ceramic, and conventional steel brakes

Hydraulic clutch systems requiring DOT 4 non-silicone fluid

Vehicles exposed to repeated hard braking and elevated brake temperatures

Drivers seeking improved resistance to vapor lock and brake fade

KEY SPECIFICATIONS:

FLUID TYPE: 100% Synthetic Non-Silicone Racing Brake Fluid

STANDARDS: FMVSS 116 DOT 4, SAE J1703, SAE J1704

TYPICAL PROPERTIES: Amber Color, Viscosity at 100°C 2.6 mm²/s, Viscosity at -40°C 1,698 mm²/s, Dry Boiling Point 325°C / 617°F, Wet Boiling Point 205°C / 401°F

SYSTEM COMPATIBILITY: Hydraulically actuated brake systems, hydraulic clutch systems, carbon brakes, ceramic brakes, and conventional steel-disc brakes

CONTAINER SIZE: 500 ml

FITMENT AND COMPATIBILITY NOTE:

Use only in brake or clutch systems requiring a non-silicone DOT 4 synthetic brake fluid with specifications compatible with this product.

Always confirm the required brake-fluid classification in the vehicle owner’s manual or service documentation before filling or bleeding the system.

A complete system flush is preferred when changing from a lower-performance brake fluid. Avoid unnecessary mixing because mixing may reduce the overall boiling-point performance of the fluid.

IMPORTANT NOTES:

Do not mix with silicone-based DOT 5 brake fluid or mineral-based hydraulic fluids such as LHM.

This product is not classified as DOT 5.1 because its low-temperature viscosity does not meet the DOT 5.1 requirement, despite exceeding DOT 5.1 dry and wet boiling-point minimums.

Brake fluid absorbs moisture from the air. Keep the bottle tightly closed in its original container and avoid using fluid from a bottle that has remained open for an extended period.

Brake fluid can damage paint, varnish, and finished surfaces. Clean spills immediately and rinse skin thoroughly with water after contact.

Fluid replacement and bleeding intervals should follow the vehicle manufacturer’s service schedule and be adjusted for racing, track, or severe-use conditions.

WHAT YOU RECEIVE:

1 x Motul RBF 660 Factory Line DOT 4 Synthetic Racing Brake Fluid, 500 ml