It's a GM fluid for manual tranny's. I'd been having issues getting into gear; part of it was the clutch, which I replaced, but sometimes the shifter was balky, and the synchromesh seems to get the best overall feedback here. So far, it feels great, but it's only been a day.
That's what I just removed: 2 bottles mt90 and 1 synchromesh.
Nope - i have had it in the box for 100K miles now.