I would suggest you look into TRAC bars, in addition to the Safe-T-Steer or Blue Ox Tru-Center.. I did. Made a BIG, and I mean BIG difference in my coach
The problem is "WAG" with a solid one piece axle (Most motor homes have) instead of Independent front suspension (Like modern pick ups) the body can move a bit si9de to side over the axle.. NOTE. not far, but it don't take much.
If the front moves one way, and the rear the other, YOU think you are going down the road cockeyed (Drifting one way or the other) so you correct, then the ends swap so you overcorrect the other way and back and forth.
The trac bar "locks" the body in position, One is good, two stop this behaviour 100$.. Ultra power makes a nice one for Workhorse or ford (I will install later) And mine is a Davis Tru-Trac on the front.
(The UP is for the rear).. I'm told the Rear one is most effective.