YOU don't need a new code, your truck(should) have a new HEX code because of the flash. Thus the reason it doesn't work. You'll need new tune/s.
This is what it says in big red letters at the top of this forum...
"IF YOUR PCM IS REFLASHED, YOUR GRYPHON WILL NOT WORK -- CURRENT CUSTOM TUNING CHARGES WILL APPLY TO REWRITE YOUR CUSTOM CALIBRATIONS!"
