Best MPG

The old Toyota based class C's get (comparatively) good gas milage. There are significant tradeoffs to achieve that, high among them being quite underpowered by any modern standards.

My Sprinter got 22 MPH , at 61 MPH .
That said , I do not believe that the thirty or forty thousand dollar premium for the Mercedes is worth it for most folks . You have to drive many , many thousand of miles to break even!

For exactly all the reasons here about gas mileage, I ended up with a Trailmanor trailer. I know it is pull behind and it folds down like a pop-up, but it is hard sided. When it opens up, it is 31 feet long.

I get 16-17 mpg with my 2005 Chevy Avalanche 1500 2WD, and 3.42 rear axle. I did the math, and the gas I will save over what I expect to drive over the next 5 years is about $7,000 over those MH getting around 9 MPG.

mdamerell wrote:
The one that is parked ;)

Yeah. Or a moped and tarp-on-a-rope.

darbyjudy wrote:
My Opinion---If you are worried about gas mileage don't even consider a RV.

I'd agree.

I have a 21 foot full height/width TT I've towed around with a small diesel SUV. First a Jeep Libby CRD, now a BMW X5 35d, when towing, I get around 14 average at 60 mph. Worst tank, 9 into a 50 mph headwind; best tank 18 with a strong tailwind.

My Opinion---If you are worried about gas mileage don't even consider a RV.

chevor wrote:
The one doing 55 on the highway.

X10

31 ft, towing, and usually overweight. 11 mpg doing 55 mph.

It's all in how you drive them.

Probably not a motorized RV by your definition, but I met a lady with a teardrop trailer pulled by a Toyota Echo, who was averaging 35 MPG. (For the non-believer, my Echo gets 43 highway if I can get non-alcohol gas.)

Matt B

Our class C 24' Winnie gets 15 MPG on diesel as long as I drive no faster than 65 MPH.

I saw a small crossover SUV with a platform tent on the roof. I talked to them and they claimed to still get close to 30mpg.

They didn't look nearly as comfortable though.

I remember being parked next to a new Kia minivan pulling a tiny Sunseker TT.
The owner told me he got 12 mpg - exactly the same as what I got with my much bigger rig.
Really if fuel efficiency is a big concern to you then RV'ing may not be for you. You'll have to decide if using a bunch of fuel will bother you.