Well, after returning on from the trip, which included the Tejon pass in southern California, having previously replaced the brake disks on the back and the shoes and calipers, and complete bleed of the brake system, I can say our brake dragging problem is resolved without slotted brake disks and our brakes no longer smell hot (the event which happened sometimes even in the city at slow rates.
I believe that the deferred maintenance by previous owners contributed to this and other issues which seem to have cropped up as we've used the coach much more than previous owners. We've put about 32 K clicks on the odometer since we purchased it, and greatly enjoy owning an RV.