Below is a general manufacturer product group description. Please note the information below is not item specific. Item specifics are above in product details.

Red Line Synthetic Automatic Transmission Fluids are designed to provide excellent low-temperature shiftability and improved thermal stability. The products identified as Synthetic ATF, D6 ATF, D4 ATF, and C+ ATF have better thermal stability and lower volatility characteristics than a petroleum ATF and provides a much lower viscosity at lower temperatures, providing much quicker shifting in cold weather. The balanced frictional characteristics provides smooth and consistent shifts for extended drain intervals. The superior stability compared to petroleum ATFs allows high-temperature operation without varnishing valves and clutches which leads to transmission failure.
D6 ATF
Recommended where the latest Dexron-VI is required, as well as where Ford Mercon SP, Toyota WS and Mercedes Benz NAG-2 fluids are specified, Red Line D6 ATF satisfies the requirements for many of the latest automatic transmissions that require consistent, low-viscosity fluids that are shear-stable.
It provides the best low-temperature shiftability in automatic and manual transmissions which require ATFs. Also satisfies API 70W/75W GL-4 gear requirements

Most shear stable for consistent operation
Excellent low-temperature shiftability

Synthetic ATF
This product is an approved GM Dexron II, Ford Mercon, and Mercedes Benz Automatic Transmission Fluid and is suitable for GM, late model Ford, or any vehicle which recommends Dexron IID or Dexron IIE or Mercon for refill. Superior stability allows high-temperature operation without varnishing valves and clutches. Also provides improved shifting in cold weather.
D4 ATF
Our most popular and versatile ATF, D4 is suitable for use where Dexron III, Dexron II, or Mercon fluids are recommended. D4 ATF is a fully-synthetic product designed to satisfy the improved low-temperature requirements which will be in the new Dexron IV specification, and the improved shear-stability requirements which will be part of the new Mercon specifications.
D4 ATF also provides a GL-4 level of gear protection, making it a superior product for transmissions and transaxles like the Corvette’s T-56. The balanced frictional characteristics provide smooth and consistent shifts for extended drain intervals. The superior stability compared to petroleum ATFs allows high-temperature operation without varnishing valves and clutches which leads to transmission failure. It’s stability allows high-temperature operation without varnishing valves and clutches. Also provides improved shifting in cold weather.
Racing ATF
Designed for use in racing automatic transmissions which need the positive shift of a Type-F automatic transmission fluid, Racing ATF contains no slipperiness additives, producing faster shifts and quicker lock-up, and can reduce elapsed time in drag racing. A higher viscosity compared to conventional Type-F transmission fluids provides higher torque converter efficiency at higher temperatures and the enhanced extreme-pressure protection provides five-times better film strength when compared to petroleum ATFs, reducing gear and clutch wear considerably.
This product can also be used in manual transmissions which require ATFs, providing better gear wear and better shiftability, but Red Line MTL® will provide even better wear protection and shift action.
C+ ATF
Satisfies the performance requirements of Chrysler Types 7176 and ATF+4 (Type 9602), while providing 30% greater operating viscosity, 1/3 the evaporation of petroleum ATFs, and improved oxidation and sludge protection. Red Line C+ ATF provides the exact frictional characteristics required in the Type 7176 specification, providing proper shift feel and proper lockup torque converter operation. The use of an improper fluid could cause torque converter shudder or harsh shifting. Red Line C+ ATF also provides the best low-temperature shiftability in automatic transmissions allowing proper shifting at extremely low temperatures andwill flow down to temperatures as low as -60°C. The improved wear protection makes C+ ATF the perfect automatic transmission or transaxle fluid for Chrysler vehicles.
High-Temp ATF
Perfect for heavily-loaded vehicles, this is a synthetic ATF which is a GL-4 gear oil for use where Dexron III or Mercon is recommended. Superior stability allows high-temperature operation without varnishing valves and clutches. Synthetic High-Temp ATF provides the gear protection of a GL-4 gear oil in an ATF and provides a higher viscosity at higher operating temperatures, allowing the transmission to operate at 70°F higher temperature and still provide the optimal shiftability and improved torque converter efficiency. The evaporation characteristics are significantly improved, being twice as good as our Synthetic ATF and five-times better than a petroleum ATF. The improved thermal stability significantly reduces the rapid evaporation of the ATF which can produce a frothing out the filler tube. The balanced frictional characteristics provides smooth and consistent shifts for extended drain intervals. The superior stability compared to petroleum ATFs allows high-temperature operation without varnishing valves and clutches which leads to transmission failure. This product can be used in manual transmissions which require ATFs and will provide much better gear protection than a petroleum ATF; however, MTL® will provide better wear protection and better low-temperature shiftability in most manual transmissions which call for an ATF. High-Temp ATF is suitable for use in automatic and manual transmissions and transaxles where Dexron III, Dexron II or Mercon is recommended.