wont shift to 5th under WOT

[pullincrazy88]

the truck is an 02 i believe. has the 8.1 liter with the 5 spd. recently tuned the motor and trans. was said that the trans would not kick into 5th gear at WOT. he had to back off the throttle a little bit and then it shifted up, but when he put the throttle to the floor again it down shifted back to 4th and would not shift up at WOT again.

this was NOT in tow hual. the TTC setings have been changed in tow haul, but were not altered in normal opperation. the only other things to be changed was the line pressure turned up. and force motor current lowered a little bit and shift times reduced.

Any ideas on what would cause this?

[GAMEOVER]

Post up the tune...

[Big Mike]

If you take a look at the stock TCM tune for an 8.1 gas w/ the Allison you'll see that they won't do a WOT 4>5 upshift UNLESS your in tow/haul.

You need to go in and hand enable it via lowering the 4>5 WOT shift speed in normal shift mode. Stock they're normally set at 158 MPH. Waaay too high for it to actually happen.

[pullincrazy88]

id say someone doesnt know there truck then lol. hes never noticed it before. thanks