We bought an olde Bounder, 31.5' with the V-10 chassis and 73k on it last summer late. We spent a lot of time getting it ready for the season over the winter. The motor has an original Banks Power Pack on it.
Our first trip was only some 250 miles round trip to the Grand Canyon and I tower our Miata on it's trailer just to check how it handled and MPG while towing.
I would say that the roads were average at best but when I topped off I was rather amazed to find that we averaged 8.02 MPG on the old timer with 5 people on board. A pleasant shock when I was expecting 6-7 MPG.
2000 Bounder 31M Class A~oldie but goodie
Acme EZE Tow Dolly towing 2017 Chrysler Pacifica