Please Don't take this the wrong way,Is this your first coach.Maybe you just need to get a feel for it and go from there.
Recently a friend of mine( non coach owner) and I took a trip using my coach.once on open road I asked if he wanted to drive a little as he is considered a Mh and wanted a feel for it.
Once behind the wheel I noticed he was "fighting the coach".My old Bounder has a tendancy to "wallow" all over the road. if you try to fight it ,,it will wear you out,nothing is wrong with my coach its just the way it is.
I Don't know really how to explain it,but relax behind the wheel,take you time and don't try to help the coach .once you get adjusted to driving it everything should be okay.
I would recommend that if coach is new to you or you are new to driving a MH, have things checked ( shocks, alignment,axle weights, tires, sway bar bushings , etc ) to make sure nothing is mechanically wrong .If nothing is found ,relax ,take your time and learn how a MH drives.