Brake fluids are classified by both “dry boiling point” and “wet

Brake fluids are classified by both “dry boiling point” and “wet boiling point.” They are also classified by US Department of Transportation (DOT) rating, DOT 3, DOT 4, DOT 5, and DOT 5.1.

Dot 5 and Dot 5.1好很多

 

Fluid                 Dry ERBP (°F)           Wet ERBP (°F)         Viscosity Limit              Chemical

Grade               @ 0.0% H2O          @ 3.7% H2O          (Cp @-40°F)                       Composition

 

DOT 3               401                          284                          1500 mm2/s           Glycol Ether Based

 

DOT 4               446                          311                          1800 mm2/s           Glycol Ether / Borate Ester

 

DOT 5 (SSBF)   500                         356                          900 mm2/s              Silicone Based

 

DOT 5.1            500                         356                          900 mm2/s              Borate Ester/ Glycol  Ether