I had a serpentine belt break with just under 9000 miles on it. I replaced all the belts back ~ 3 years ago. The belt used was a Gates Micro V K060525 which their computer lists as 'Except motorhome'....
Bearings fell out of mine on a backroads highway down near Death Valley about 100 miles from no-where. Belt broke, I ran genset with jumper to chassis bttery to get to main highway. Tried to overheat, so disconnect toad and had Boss drive toad.