CSF Racing Race-Spec Dual-Pass DCT Transmission CoolerBMW F8X M3 M4 M2 Comp (DCT) Transmission Cooler The engineers at CSF know cooling. So when it comes to keeping your transmission temps down as you push your F8X M3 M4 M2 Comp hard on the street or track, the CSF Trans Cooler is the obvious choice. With an increase in cooling efficiency of around 30%, you can drive with confidence knowing you won't be damaging your expensive transmission due to overheating. The CSF #8081 Cooling product is designed to