Class A vs class C

On our latest trip of about 3,000 miles we averaged 9.1 MPG But we also ran the generator for at least 80 hours.

Mileage keeper shows my C (E-450, 30', heavy with 2 slides) averaged 8.2 MPG over the past 30,000 miles. Individual tanks ranged from 6 MPG to 12 MPG, determined mostly by speed throughthe air, whether determined by road speed or headwinds and tailwinds. A 30mph tail wind will do wonders for MPG on a 70 mph road. A 15 mph headwind will kill MPG when you are going only 55. But it all averages out, in the longer term.

I just spent several hrs figuring out my MPG over 70,000 miles of driving. What I did was eliminate gen-set usage over 2 hrs per tank full such as storms like Sandy and eliminate readings where I was working on engine problems where there was excessive idling or driving. I was surprised at the findings. My M/H weights about 16,000 lbs fully loaded,is 33 ft long with one slide and has a 454 tbi with Thorley headers, free flow muffler, and CAI. I averaged 9 mpg over all. when I looked at the data what I saw was that I got higher mpgs for the first 30k miles by .5 mpg. I got better mpgs in the mountains than on flats because I think it takes less average energy to go up hill than downhill. Towing a 2800 lb Toyota Corolla made no difference in MPG's. The worst mpg was 6 and the best was 12.6. The worst average was in Alaska 8.3 because it was hard to stay in 4th gear because of the roads. The best was traveling back and forth to Tn from Ct on I81 again I thing because of the longer less steeper grades found in the west (10 mpgs). Most of my camping is dry camping and have noticed less mpg when my batteries are somewhat discharged (Alternator working harder). I usually travel with a full tank of water and ave 62 mph. I do have 225 /70 19.5 tires and don't know if that is affecting the mileage readings.

My 31ft class C with the V-10 around six pulling a toad. On flat land around 9.7 and in the mountains about 7.8 mpg. This is without a toad. I keep the speed at around 60-65. Of course mountain travel is slower. I try to travel with waste tanks empty and a bare minimum in the fresh waster tank.

Our 1985 26' Class C got 6 mpg at sea level and about 4.5 at altitude. It had a carburetor-equipped Ford 460 and the 3-speed automatic.

Our '02 32' Class A gets around 8 mpg wherever we go, with the V-10and the 4-speed overdrive automatic.

We don't pull a toad.

Not much relevance to this question without considering driving style, weight and a lot of other factors. And on top of that I don't get any gas mileage.

But 44K lbs with the diesel I get 7.4 MPG of diesel.

The cost per mile for fuel is going to be a function of the gross weight of the MH when fully loaded and how fast you choose to travel down the highway. The average Class B+ is going to get better distance from a gallon of fuel than the average Class C which is going to do better than most Class A motorhomes.

Want the best possible fuel economy then get a Roadtrek built on the Sprinter platform and powered by a Mercedes diesel. These get 22 MPG or better but they cost more for their size than their larger brethren on the highway.

A good compromise are the B+ motorhomes with one or two slides. Lots of space and a sleeker profile and medium load for the engine going down the highway.

A Class A will more often require a diesel which costs more up front and more to maintain and makes finding fuel stations much more of a challenge.

A big consideration is how you plan to use the MH. Quite a difference between going to one spot for weeks at a time and traveling from place to place and only spending 2-3 days at each spot on average.

Another aspect is that any RV longer than 28' is going to limit the campsites you will be able to use and even the turnouts where your MH can fit.

Gotyer6 wrote:

Dakzuki wrote:
15 mpg

What in the hell are you driving? I need one! That's just shy of what my jeep gets!

A diesel Sprinter based class C.

Right Bobbo, I did the same thing when we made a trip out West a few years ago and I confirm you data. That's why I now drive right around 62 MPH and my grandson thinks the world is passing us by. I tell him the less I spend on fuel the more I have to spend on him.

8 to 10 for a gasser, a little more for a diesel. However, since diesel costs more, you get about the same mileage per dollar.

I once ran a test. I get 8 mpg at 62 mph. I once did a 2,000+ mile vacation driving 72 mph and got 6 mpg. That is a 25% drop in mileage for a 15% increase in speed. Not worth it.