How many versions of ecu tuning are out there for the 6.4? And how can you figure out what you have and what someone else has? I Bought a tuner with custom tunes on it and none of them work on my truck. Kind of frustrating. Are tunes locked to vin so they only work for one customer vehicle? I.e. you unlock and unmarry your tuner, sell it to me, can I run the tune if my ecu has the same strategy? I can either buy new custom tunes or buy another used tuner for a little more (newer tuner as well, and cheaper than new) and hope his tunes work on my truck. If they don't, I still have to go buy custom tunes and more money in the pot. Yay.