hey guys usually when im on the hiway at about 72 to 75and going to pull a hill it kicks down to about 3500 rpm from about 2500 and sometimes it dont like to shift back to od. i was just in the computer and found the tire size was set for 245-70-16 so we changed it to the proper size 275-70-17. it is usually on cruise control when this is going on.also seems to be low on power at those speeds. i have almost 50psi fuel pressure(new pump) am i dealing with a cruise control problem or tranny issue or what else could it be.. thanks for your help guys

 

Mine does the same thing and I have 285/75/r16's with 4.10 gears. I dont even let in od when pulling anymore. when not in od it pulls like a champ and 70-75 mph.