Any 6L90 experts here?

[YoungPup1977]

If you plan to go the used trans approach, I would suggest to reuse the TECHM from the original trans. This way you eliminate the mismatch of information from PCM and the Trans TECHM. The TECHM is bolted to the VB, the pressure switches can be tested via ohm meter before installing the VB back onto the used Trans.
Good Luck !

[rustyrodknocker]

That's great to know, thanks. I will indeed do that if I purchase a used unit. This scenario has been a huge learning curve since a month ago when I drove it home thinking it had a 4l80e. I thought I had a good grip on it until I learned there is a thing called a 6l90. The side effects of having never owned a late model vehicle I guess.