No! Generally the tubing used in transmission oil cooler coils is too small and may restrict the oil flow. You can, however, use an engine oil cooler coil for transmission oil. Top What size engine oil cooler do I need? The best-suited engine oil cooler to use is determined by the horsepower output of the engine. Estimate the engine's horsepower and refer to our catalog. Top What do I do if I don t have any space for an engine oil cooler? Perma-Cool has a wide variety of oil coolers, including some designed with electric fans attached that will allow you mount the cooler almost anywhere. Top Is there any oil cooler that will cool the engine and the transmission oils at the same time? Yes. Perma-Cool has Dual Circuit oil coolers with or without an electric fan that were specifically designed to cool two fluids at the same time.