When I bob-tailed up to Show Hauler and back (540 miles) I used approxiamately 40 to 45 gallons of fuel. I do not have a computer like the newer Volvo's and I fill the tanks to 95% so this is not super accurate. That is approx 12 to 13.5 miles to the gallon and was consistent with the 2 fill ups I made during the summer. I don't think it ever fell below 3/4 of tank.
I can't imagine I will drop below 10 mpg with the conversion on. I have twin 150 tanks which I really like, I don't have to worry about fuel on most all outings. And I really don't mind the thought of carry fuel which may not get used. My mileage would not increase all that much that it would offset worrying about where to get fuel in a strange place.
What method are you going to use to build your own, Steel or FRP?
Any details would be great for others as well as I would love to see the progression of the project. I originally considered doing a unit on my own, and I am glad I did not. There are a ton of items I never considered when I began to plan the conversion, you may have more experience in fabricating than I do. Once I fabricated a new interior in my truck I was really glad I chose not to do it. Just would have taken way to long for me to finish it.
Bill
2003 28' Show Hauler Motorhome on a 1995 FL 120 completely refurbished chassis.
Currently in production - scheduled completion 1/10/03 www.showhauler.com