Transmission Service Tips Transmission Fluids Transmission fluid should be changed while doing the 30,000 mile inspection. Changed again each 30,000 miles or about every two years for long life. 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, a hydraulic fluid for the control system inside the transmission, a heat transfer medium to help maintain proper transmission temperature, a lubricant and a energy transfer medium for bands and clutches. Because of these demands we recommend fluid changes no less than every 30,000 miles.
Transmissions withstand the torture of summer heat and winters slip and sliding.
Not to many years ago only two types of automatic transmission fluid 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.