should be changed while doing the 30,000 mile inspection.
Changed again each 30,000 miles or about every two years
Automatic Transmission Fluids
Automatic transmission fluids must perform many demanding functions.
These include helping transfer power from the engine to the transmission
via way of the torque converter, hydraulic fluid for the control system
inside the transmission, a heat transfer medium to help maintain proper transmission
temperature, a lubricant and energy transfer medium for
bands and clutches.
Because of these demands we recommend fluid changes at about
every 30,000 miles or the factory recommended mileage for severe conditions. Transmissions withstand the torture of summer
heat and winters slip and sliding.
Not to many years ago only two types of automatic transmission fluids were
used. Type 'A' was used in General Motors vehicles and Type 'F' in Ford.
Today the specifications change from year to year and by manufacturer. Consult your owners
manual or a shop manual if in doubt.
Modern ATF typically contains a wide variety of chemical compounds intended
to provide the required properties of a particular ATF specification. Most
ATFs contain some combination of additives that improve lubricating
qualities such as anti-wear additives, rust and corrosion inhibitors,
detergents, dispersants and surfactants (which protect and clean metal
surfaces); kinematic viscosity and viscosity index improvers and modifiers,
seal swell additives and agents (which extend the rotational speed range and
temperature range of the additives' application); anti-foam additives and
anti-oxidation compounds to inhibit oxidation and "boil-off"
(which extends the life of the additives' application); cold-flow improvers,
high-temperature thickeners, gasket conditioners, pour point depressant and
petroleum dye. All ATFs contain friction modifiers, except for those ATFs
specified for some