I have or should i say had a 93GMC 1500. sence i bought the truck i have swapped out the suspension with a 1ton, upgraded the cooling systems,installed a 5th wheel and goose neck.
The new transmission bolted up fine to my 5.7L motor .My problem is i have already taken out my factory 4L60e and put in a 2000 4L80e. I am thinking that the to unused pins in the connector go to the front sensor. If this is true then it would explain the incorrect shifting.
It could also explain the weak forward gear or the incorrect shifting it is doing.



Work in progress converting 1993 GMC 1500 into a 3500
(grease monkey at heart)

 

So when do you swap your 1500 frame over to a 3500 frame?

:P