I recently purchased a new Superchips Flashpaq 2845 and overall like the power increase. But I have had to perform a series of reprograms because it has an issue when shifting from 3rd to 4th of hammering the shift feeling like it is ripping the tranny out... I have tried different shift points for 3-4 to no avail. I am curious if adjusting 1-2 and 2-3 to a specific mph+ as well would make a difference in the 3-4 shift. Ultimately if I can't find a program that tames that shift point down this was a junk purchase and would really feel bad selling it to someone else. If anybody has a program that works for this it would be greatly appreciated if you shared it... Thanks