I tuned a 2013 gmc sierra 1500 for a friend of mine. It has the 6.2/6L80 combo. It shifts perfect other than the 3 gear down shift from 6 to 3. Is there anyway to keep this thing from down shifting to 3rd it makes plenty of power to not have to down shift 3 gears to pick up speed. I have tried moving the mph of the shifts up and down both as much as 6 mph and it still does the 6-3 downshift at 60% throttle or greater. Anyone have any sort of insite with this it?s starting to drive me crazy.