My Class C Majestic is loud and all over the road!

I am guessing you have a Ford chassis? First, check air pressure in your tires. Then take it to a real alignment shop and have it setup. Then look at shocks.
As for noise? Not much you can do. A full undercoat might help some. Most of the noise is stuff you cannot control Im guessing. Unless you start walking around while someone else is driving and start identifying squeeks, and rattles you are basicslly SOL.