In almost all vehicles with an automatic transmission there is a transmission cooler placed inside the radiator. Most standard transmissions do not make as much heat and therefore do not have a cooler. The cooler for the automatic transmissions are placed inside the radiator, the reason behind this is the antifreeze provides the perfect environment. It warms the transmission up with it’s cold and keeps it from getting too hot in extreme heat.
An auxiliary cooler is a completely separate transmission cooler that is typically mounted somewhere in the front of the AC condenser. While these coolers are helpful they are not quit as effective as the coolers that are mounted inside the radiator. The reason? The auxiliary cooler is cooled by air flow while the cooler inside the radiator is surrounded by antifreeze which is a controlled environment.
For this reason we recommend never eliminating the cooler inside the radiator. If you want to increase cooling capacity we recommend adding an auxiliary cooler. This way the transmission is being cooled by two different coolers; one with antifreeze and on through air flow.
In very few cases the cooler for the transmission is located externally from the transmission.