Transmission Coolers, Lines, and Fittings

Transmission coolers, lines, and fittings are necessary in order to keep transmission fluid cool in automatic transmission applications. It is important to use the factory cooler size or larger, depending on the vehicle's GVW. Too small of a cooler will cause elevated transmission fluid temperatures and decrease transmission service life.

The best transmission cooler is one that closely matches the gross vehicle weight (GVW) of your car or truck or is slightly larger. This helps keep transmission fluid temperature down, lengthening its service life. The gross vehicle weight is the total weight of the vehicle, fully loaded with passengers, fuel, cargo, etc. and is usually identified on a door or doorjamb sticker. The best line fittings and size is determined by the application, transmission, cooler, and radiator sizes.

Transmission coolers range in price between $30 and $1,000, depending on size, attached cooling fan, and other options. Universal transmission cooler lines range in price between around $10 to over $50 and transmission cooler line fittings ranging in price from under $10 to around $40 each.