Width is also an issue. Our Class C is fairly short (24 feet), but it's 101.5 inches wide.
We have had to pass-up going down some desert roads that, although firm enough and wide enough for only our RV, would not have allowed anyone to pass without having to pull off into soft sand.
For the best flexibilty in boondocking, I would stay less than 93 inches in width at your rigs widest part (not counting the mirrors, because most of them can be folded in).
Regarding height of our RV, we do carry pruning equipment along for too-low branches.