Automatic transmission fluid
It is formulated to ensure smooth valve operation, minimize brake band friction, facilitate torque converter function, and provide effective gear lubrication.
ATF is commonly utilized as a hydraulic fluid in certain power steering systems, as a lubricant in select 4WD transfer cases, and in modern manual transmissions.
[citation needed] The friction modifier means that the fluid sticks to the surface of the metal slightly stronger, and therefore only helps to prevent early wear.
In many countries, Ford has said that the modern Dex3 fluid is fine for the same transmissions that it says require the older standard.
The vehicle's owner's manual will typically list the ATF specification(s) that are recommended by the manufacturer.
Synthetic ATF is available in modern OEM and aftermarket brands, offering better performance and service life for certain applications (such as frequent trailer towing).
Using a lint-free white rag to wipe the dipstick on automatic transmissions is advised so that the color of the fluid can be checked.
Dark brown or black ATF can be an indicator of a transmission problem, vehicle abuse, or fluid that has far exceeded its useful life.
The world's first mass-produced automatic transmission, the Hydra-Matic 4-speed, was developed by General Motors (GM) for the 1940 model year.
In 1966, Chrysler began releasing their own automatic transmission fluid specifications; see Mopar ATF for more information.
[citation needed] From the 1940s through the early 1970s, ATF contained whale oil as a rust and corrosion inhibitor.
[11] A moratorium on whale oil at that time prevented the continued production of older ATF such as the original 1967 DEXRON formulation (Type B), and the fluids which preceded it.
This fluid was developed to modify the vehicle shifting characteristics and to provide considerable improvement in the oxidation resistance and anti-wear performance.
The 1974 Ford Car Shop Manual reads "The automatic transmission is filled at the factory with "lifetime" fluid.
[14] The November 1954 edition of Lubrication Magazine (Published by The Texas Company, later known as Texaco) featured a story called "Evolution of the Chrysler PowerFlite Automatic Transmission."
The fluid operates under almost ideal conditions in what is essentially a hermetically sealed case; the small amount of atmospheric oxygen initially present is removed by a harmless reaction with the fluid to leave a residual inert (nitrogen) atmosphere.
Lifetime automatic transmission fluids made from higher-quality base oil and an additive package are more chemically stable, less reactive, and do not experience oxidation as easily as lower-quality fluids made from lower-quality base oil and an additive package.
Therefore, higher-quality transmission fluids can last a long time in normal driving conditions (Typically 100,000 miles (160,000 km) or more).
Always consult the vehicle maintenance guide for the proper service interval for the fluid in your transmission and your driving conditions.
