I was under my 2009 Greyhawk I can not believe how much the rubber body mount cushions are deteriorating, they are not only compressing they are starting to split, wish they made a two piece replacement made from polyurethane. This is not a easy fix.
I knew they made them, its the body from frame that is troubling.I have tools to replace them. You would have to break the seal around the cab to jack up the coach.