Re: 45RFE to 545RFE upgrade
Yes, there was a flash a long time ago which added a 5th gear to the 45RFE, making it the 5-45RFE. Wouldn´t it be cheaper to just let the flash be installed by the stealer, then buying an other TCM?
Also the TCM keeps the CVI´s in its memory (clutch volume indexes), which it uses to calculate the shifts. If you would put an other TCM in, then a quick learn should be performed, using the Stealer DRBIII scanner, to reset all the CVI´s. The TCM will then relearn the shifts quickly. If you don´t do this, it will eventually relearn the shifts, but it can take quite a while and you can have some hard shifts until it relearns.