2017 GMC Sierra, 5.3, 6 spd auto, Z71, 72K Mi.
Hey ya. Currently no MIL because I cleared codes from a misfire after changing plugs. However, the transmission has started shifting clunky especially in the 3-2 and 2-1 (presumably) downshift. Fluid level seemed low, because it is almost clear so I added. Now it seems overfull and I'll suck that out tomorrow. Dexron VI, yes.
I put my XTool D8 on it and drove it around doing the "Live Data" for the engine and then for the transmission. Admittedly, I don't know how to use that darn thing very well.
I drove it until the transmission temp was almost 160. The only things that it showed that were alarming was the 5V Reference is 5.01 on all of them, and (biggie) ECM (or ECU I forgot) Failure 2.
Clue me?
That's only 1/100 volt from nominal 5 volts. Actually pretty remarkable given the challenging electrical environment in a moving vehicle. I wouldn't lose any sleep over it.
2017 GMC Sierra, 5.3, 6 spd auto, Z71, 72K Mi.
powertrain warranty is 5 years. Maybe you're still covered.
Dexron VI, yes.
That should be what is specified in your owner's manual.
5V Reference is 5.01
close enough.
ECM (or ECU I forgot) Failure 2.
no idea what this means.
I don't know how to use that darn thing very well.
shift delay time , line pressure, transmission input & output speed would be relevant. but it won't mean much to you without knowing how everything works. I would take it to a pro. At 72k you are due for fluid & filter change anyway.
