Performance Friction RH665 DOT4 Racing Brake Fluid

Guaranteed highest minimum dry boiling point of any DOT4 brake fluid

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  • Dry Boiling Point = 325° C (617° F)
  • Wet Boiling Point = 184° C (363° F)
  • DOT4 (exceeds DOT5 specs)
  • Normal viscosity
  • 500mL bottle

Racing brake fluid with the highest guaranteed minimum dry boiling point (ERBP) of any DOT4 Brake Fluid

Performance Friction RH665 Racing Brake Fluid is a cut above other racing brake fluids and it’s specially formulated for racing applications where braking systems operate at very high temperatures. The complex mixture of Glycol Ether Borate Esters and Polyalkylene Glycol Ethers, together with advanced corrosion inhibitors, antioxidants, and other modifiers, result in an exceptional brake fluid with not only a very high boiling point, but which also conforms to all DOT4 specifications. All this while maintaining its class-leading viscosity, lubricity, and compressibility performance at extreme temperatures to ensure braking system reliability, performance, and a rock hard pedal.

RH665 has the highest guaranteed minimum dry boiling point (ERBP) of any DOT4 Brake Fluid, 325°C, to guard against vapor lock and give a rock hard pedal even under extreme racing conditions. Many manufacturers quote boiling points, but don’t be deceived - this isn’t the minimum specification that you could receive and can simply be the result of a single test sample. Typical values for RH665 are invariably higher than 325°C, and the same applies to wet boiling point where RH665’s is guaranteed to be above 184°C, with typical values much higher and equal to or better than other leading brands.

Normal or Low Viscosity? For the track it's always Normal Viscosity brake fluid. This is because Low viscosity fluids will be too thin once exposed to typical track temperatures. For regular road and street use, however, you should use whichever fluid came from the factory. The cutoff between Normal and Low is not by model year. If your chassis existed before 2004 it uses Normal viscosity (all chassis up to E53). But if the chassis was introduced after 2003 it will use Low viscosity fluid (all new chassis starting with E60). The lone exception is the E53 X5 which could take either: 1999-2003 X5 uses Normal; 2004-2006 X5 uses Low.

RH665 can safely be mixed with other DOT4 brake fluids, however this will degrade the exceptional properties of RH665.

RH665 isn’t suitable for use in contact with magnesium components or in mineral oil based systems.

For best results bleed the system with fresh fluid before each event and when the brakes have been excessively hot and/or the conditions are especially humid. Always follow the vehicle manufacturer's recommendations.

Sold in 500mL bottles for maximum freshness.

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