When we did it was behind a 1963 Studebaker 3/4 ton Pickup we towed a 1986 17 1/2' Bigfoot
Trailer, what we found on that trip was the size is to wide and the Automatic I installed was not a good fit as the friend I bought it from said it was rebuilt but turned out not to be so. By the time I towed it to Omaha and back home to British Columbia the oil had turned blue from all the Climbing up into Mt. Rushmore, but the MPG with that big old 289V8 with a Carburetor got 11mpg on the hwy. I only time it got worse was in bad wind which we came across a cple of times and got a lot less. When I got home I spent $5000.00 on a brand new 700R4 tranny which was what I should of done the first time around.
We now own a 1999 Rexhall Vision 25.6' with all the bells and whistles and my wife's favourite item is the walk around queen bed, I also like that feature as no more crawling around and trying to get out of the sack when one needs the Loo at 3am in the morning in the dark. We now tow a 1996 Suzuki X90 that we tow behind the MH which has a V10 or 305hp with automatic this last trip out we averaged 10.3 Canadian mpg with the car on flat tow. Prior to not towing a tow'd we got 12.6 Canuck mpg this is combined travelling in Canada and the USA we travelled 5375 miles.
Best priced gas we bought was in Iowa in a little burg called Clearwater for $1.85.9 gallon lucky for us we filled up the MH took 63 gallons next day at the car show the price was $1.87.9 still not bad and we got 8 gallons in a 10 gallon tank and we were the only Suzuki X90 out of around 1000 cars. The Toad gets around 27mpg with it's 1.6L motor weighs 2400#'s all in all it is a good travelling companion to have when one wants to do bit of sight seeing in the area your are in.
We did 3 provinces in Canada, then USA ND, MN, IA, MO, KS, CO, UT, WY, MT, ID, WA, and home to BC. Saw some real great places we travelled a lot of secondary roads and did one hell of a lot of climbing and if you have never driven with a V10 then your in for treat if you ever do. This is one tough motor and when it dies it is cheaper for us to buy and new MH we now have 89,000 miles on er and she is still roaring like the lion she is.
Our Soon to be new flat tow toad will be a 2010 Suzuki Grand Vitara 4wd it weighs in at 3700#'s and is a 2.4L engine automatic. Because most vehicles today come with a CVT transmission you cannot flat tow them so then u need to have a automatic with 4wd put the transmission in Park and 4wd in N and set up the Brake buddy and away you go.