You can not change the Trans tune on the fly. That is a download that is for your powertrain module. You can only change the power levels for the engine on the fly. You have to reload the engine and the Trans again to change the Trans tune. The hot Trans is the best tune to run for the HotX engine tune. It will be really aggressive at first but give it 2 weeks of everyday driving and you will love it. The mild Trans tune for me does not handle the HP as well in my opinion. You need the hard shifts to protect your clutches.