no up shift [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: no up shift


bigwhitehd
01-31-2007, 05:53 PM
Alright..truck is a 02 lb7 with a hot edge, 37's, and 100k miles. in level 3 the truck wont up shift a locked shift...like 2locked, to 3rd locked....in any of them, just goes up to redline stays there and wont shift until i back out of it....level 1 shifts fine....its somewhat cold, running a bigger trans cooler with fan off, trans at different temps from 100-150. hasnt done this in the 20k miles i have put on this truck with this chip, till now. Never limped the trans, never slipped the trans, truck is well taken care off... fuel filter maybe? give me some idea's.

thanks, charlie

bigwhitehd
02-01-2007, 11:19 AM
anyone?

Kennedy
02-01-2007, 11:36 AM
Change your fuel filter, and consider adding a good lift pump setup.

Diesel Tech
02-01-2007, 12:44 PM
Have you tried it in both Tow/Haul and Normal mode? Make sure the transmission has some heat in it before you do it. If you have a scantool take a look at the vehicle speed to make sure it working OK also check your fuel filter.