When I mowed for my Mom-in-law there was a hill that I really shouldn't have mowed across. As long as the grass was dry it was possible in 4WD. I usually used the old Ford on the hill because I could keep one cheek on the uphill fender and the other on the seat. The RFM doesn't allow any twisting between it and the tractor, so it was pretty stable so far as rollover from the slope itself. Even in good conditions the tractor tended to "crab" along the hill. My one fear was that I'd slide sideways. There was a concrete retaining wall atthe base of the hill that was flush with the ground I was mowing. The ground on the lower side of the wall was about 18" lower and the rusty pipe fence at the bottom would have served no purpose other than to be something to hurt on the way through it. A few times when the grass was damp it did start to slide. I steered sharply uphill and floored it and the tractor got itself pointed uphill.
Here's a pic and it doesn't look as bad as it really felt. That may be partly due to the utility pole behind me being out of plumb.
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