sum guy

iTrader: (4)

I have a truck 4l60e and in manual first non wot it shifts at about 4k. If you are in manual 2nd it will down shift to first at wot. Is there a valve body or PCM mod I can do to fix this?

bwkmaro

transgo hd-2 shift kit but unless you mess with the computer or get a hd-3 kit, it will always down shift from 2nd to 1st

sum guy

iTrader: (4)

Well how much could be accomplished though tune only? That would be the easiest route.

joecar

It depends on the tuning software and the calibration id...

some calibrations have tables for Manual 2nd 1->2 and Manual 2nd 2->1 which can be edited to prevent those shifts.

Not all software packages show those tables for all calibrations (some only have one of those which doesn't help).