Cnile, I am running a finned heat sink type tube trans cooler and I am also running a back up Derale tranny cooler with a fan which comes on via a temp sensor. The reason I am running two tranny coolers is because I am not running any trans cooling in my radiator. It may be over kill to run two coolers, but I have peace of mind knowing my pro built th400 will stand up over time and not be killed by over heating.