Since the final viscosity after use of these fluids are similar, Dexron VI fluids can be used where Dexron III fluidswere previously recommended (with the exception of some manual transmission applications, our customers report).ĭ6 ATF also provides significantly improved gear protection and will provide a GL-4 level of gear protection. Red Line D6 will drop to no less than 6.1 cSt. Rather than beginning with a 7.5 cSt fluid and allowing a viscosity loss in use to drop to 5.5 cSt, the Dexron VI fluid requires a starting viscosity of less than 6.4 and a final drop to no less than 5.5 cSt. Dexron VI requires a different approach to a conventional ATF formulation. Synthetic D6 ATF is a lower viscosity version of the D4ATF and is designed for better fuel efficiency in CAFE testing.
To confirm, check the decal located on the side of your transmission. This is the transmission fluid used in both manual and automatic transmissions since the mid-2000's. This is Red Line's latest synthetic transmission fluid that is compatible with BMW's MTF-LT3 transmission fluid. D4 is similar to Red Line's MTL formula and can be used in many BMW manual transmissions where MTF or MTF-LT2 is called for. The superior stability compared to petroleum ATFs allows high-temperature operation without varnishing valves and clutches which leads to transmission failure. The balanced frictional characteristics provide smooth and consistent shifts for extended drain intervals. D4 ATF also provides a GL-4 level of gear protection, making it a superior product for transmissions and transaxles. Synthetic D4 ATF is suitable for use where Dexron III, Dexron II, or Mercon fluids are recommended.
D4 ATF is a full-synthetic product designed with superior low-temperature properties compared to a Dexron III® fluid, and the improved shear-stability requirements which are part of the Mercon V® specifications.