its not slippin i actually downshifts into 2nd, with my foot in it. guy at the tranny shop said it might be the trans module. we'll see next month when i regear it, maybe that will solve it.

 

The TV cable adjustment affects the kickdown and how soon (or late) the truck shifts.

 

Sounds like your front band is slipping, drop the pan and with a flash light check for delamination of your front band, if it doesnt tighten up around the drum (servo activated with pressure)it won'tdownshift rightand the truck will redline and gain no speed. My old tranny did this, didnt know what was going on till I replaced it and tore the old tranny down.

 

I'd try the TV cable, and check the TPS just to be sure.