Yukon goes limp to where you have to shift from 1st to 2nd and that's all you have
I have a 94 Yukon that I've switched the computers
and still no luck no one sells a chip stock chip for it
so when I when it's cold he'll run fine until you go
over 50 miles an hour then you'll lose overdrive
forth and third gear then you have to shift from 1st
to 2nd and that's all you got what could be my
Could be the TCM or shift solenoids, when they warm up they go into thermal failure, you could save yourself a headache if you just take it to a good tranny shop so they can run their standalone tests on the tranny and TCM, then they could tell you if it is the solenoids,TCM or an internal pressure problem.
If it's acting like it's in neutral when it should be in 3rd or 4th then you need a rebuild. If it's just hanging in 2nd gear then it's most likely a faulty shift solenoid.
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