Done with conversion, but now major tranmission problems!

[PitchBlackC3]

IIRC, there was something weird about 95 and then all 96+ are PWM.

[Bellflower]

i get conflicting storys if the 96 is modulated ot that started in 97, the case was redesigned in 97, but not sure of internals, I do keep hearing rumors of a pin difference(1 wire in the main connector), but no one can confirm if that is true or not. This is extremely frustrating, trans worked fine behind other motor and computer, so it should be fine behind this one, but its not. I dont wanna put a TH350 or 700r4 in it, but im not gonna dump 2 grand in a 4l60e that may do the same thing

[PitchBlackC3]

I just looked in my GM manuals and it shows 96 and 2001 have the same pin out on the round trans connector.
Also lists PWM on the 96.

[MrHorsepowerLSx]

Have you tried to not using the nelson harness and just plug in the 01 harness directly into your trans ?

[scarybowtie]

The 95 and up plugs will work. Do you have the new computer controlling everything? As far as speedometer and things go? My truck is a 95 so it is different but I had all kinds of problems with my trans as well after the swap, until I tied my factory vss wires in with the ones on the new harness. Have you done that? Hope this helps. GL