ive got an 03 super crew 4x4 with the 5.4 and ive had to turn my programer back to stock
the problem i was having is that on any setting it made a horrible squeal when it shifted and on high throttle take offs it shutters
any info on fixing this is appreciated
Gary

 

My truck would do this too along with many others when shifting 1-2 and 2-3 on WOT. I Switched out my serpentine belt with a Goodyear Gatorback belt and the squeeling went away...