For those of us with automatics, It seems that the heat exchanger, which is connected to the radiator, is the only means of controling transmission temps.
During race conditions, the heat from the transmission fluid mirrors water temps, and is a burden on the system. I was wondering if it was possible to remove the heat exchanger, and instead, install an automatic transmission oil cooler. This would be a far more effective way of lowering ATF temps, and would also free the radiator from the added heat load. Oddly enough the DCT in the 335is, also has a heat exchanger. This is why they gave that car an extra 0.5L radiator capacity. Still in both cases both transmissions would see increased an increased life span with a seperate oil cooler.
http://www.ecstuning.com/BMW-E46-M3-...05/PriceAlert/