Max, a good friend of mine was there in September doing 4 wheeling in a Cherokee... Check this link to his pics and short narrative:
Moab link
When the page opens, use the right side scroll bar and go about 2/3 of the way down; you'll come across some notes about Kanes Creek Canyon... From the pics shown, I doubt you want to take your coach down there, not to mention pulling a trailer. -But then again, I could be all wrong; perhaps asking a local would be your best advice.