New here, new to Gravely mowers. Long story short, my father had bought a Gravely 20G Professional, not sure what year it is. Dad recently passed away from an unexpected heart attack, but before he died, apparently he had tried using his bush hog behind the Gravely.
I don't have the mower in front of me, and it's not easily accessible-I live two states away from my mother's house. The problem is at some point after dad had used it with the bush hog, something happened to the tractor. It will run and drive, but as soon as you hit an uphill slope with it, it pretty much stops. The only way to get it going forward again is if you drop it in low range, 1st gear, and even then it barely pulls itself out of its own way. This is with only the belly mower attached, not even with the bush hog.
I'm trying to understand a bit more about how the 20G works: I originally thought it was a hydrostatic drive, but some internet research seems to lead me to believe the G designator means it's a gear drive transmission. I'm hoping to get some ideas of how that tractor operates and what might be a problem, before she has to take it to a dealer to fix it, or sell it broken, and take a huge loss on it. Any assistance anyone here could provide would be greatly appreciated.