Im trying to firgure out why my PCM is not reading the GND on Pin16 while in 4Lo, shifting is erratical, upshifts way too fast and no downshift even if WOT.
Im leaning to think its because the PCM was in a AWD application with no 4Lo application (even if 4Lo tables are available in the tune?) and now its running the same 4L65 backed with a 4WD transfer case with 4Low with a VSS is in between Tranny and transfer case.
What would you recommend? Segment swap? System or transmission segments?
Thanks for your inputs.

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