F 350 2WD Super Duty V10-6.8L VIN S (1999)
Transmission Cooler: Description and Operation
CAUTION: Do not attempt to backflush and clean the oil-to-air fluid cooler. The OTA fluid cooler must be replaced as part of a
transmission overhaul, or transmission damage may result.
All vehicles with automatic transmissions are equipped with an Oil-To-Air (OTA) fluid cooler. Vehicles equipped with the 5.4L engine are also
equipped with a cooler that is integral to the radiator. In operation, transmission fluid travels from the transmission to the oil-to-air fluid cooler then
back to the transmission. The oil-to-air fluid cooler transfers heat from the transmission fluid to outside air.
On vehicles equipped with the 5.4L, engine, transmission fluid travels from the transmission to the integral cooler in the radiator then to the OTA fluid
and back to the transmission.
The integral fluid cooler transfers heat from the transmission fluid to the engine coolant.