Hey guys. So I'm attempting to reflash a T43 (programmed by GM July 2018) with a different CTZ file that has the same OS, but a different Calibration (older) number. A CALIBRATION ONLY or FULL FLASH still will NOT change the Calibration number , the VIN, or the Transmission Diagnostics.

Is it accepting the calibration changes and not showing? Is the Calibration number actually the part number of the T43 module? Can I not change calibrations?

V2 and AutoCals are up to date.

HELP!!