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BillyandKris's avatar
BillyandKris
Explorer
Aug 10, 2021

Opinions on diesel vs. gasoline

Asking advice/opinions: Considering getting a Class C motorhome. We have had diesel truck with fifth wheel for many years. Diesel=power/torque. We travel a lot in the mountains-especially Colorado. We want a Super C, but not sure can afford. Second choice is a Jayco Greyhawk (gasoline engine). Looking at 30-32’ choices. We would flat-tow a Jeep Cherokee. Will we be sorely disappointed in a gasoline engine or should we stick with diesel?
  • Could always rent a 32’ gasser that has s hitch. Try it. It might be money well spent with no regrets.
  • BillyandKris wrote:
    Will we be sorely disappointed in a gasoline engine or should we stick with diesel?


    Will YOU be sorely disappointed? I suspect from the framing of your post that the answer to that is quite possibly "Yes". ;) Would I? Probably not.

    It's a pretty subjective question that I believe only you can answer accurately.

    As is often stated here and I concur, THE most important part of a motorhome is the floor plan. Find a floor plan which your wife find livable, both on the road and while parked. Well, mostly your wife...but it's OK if you like it too! LOL :)

    Also make sure that it is on a chassis that can carry the intended weight and have adequate tow capacity without exceeding the manufacturer's ratings. If you can find all of that AND get the diesel and it is within your price range, then go for it.

    But if finances require that you are given a choice between a gasser with the ideal floor plan and a diesel with a less than optimum floor plan, I'd take the ideal floor plan with a gasser.

    Good Luck in your search,

    ~Rick
  • jdc1's avatar
    jdc1
    Explorer II
    Are you trying to get your wife on board to spending extra dough on a Super C? LOL.
  • I spent the part of my career ashore in engine test labs in Detroit. Until then, I was running the engines of iron boats on the lakes. Without any doubt, I can tell you that the advantage most diesels have is the turbo-supercharger that makes altitude a big non-issue. Without that, there is only the slight gain in fuel economy. That is almost covered by the other maintenance costs.

    I didn't tell you that I have owned diesel cars and trucks most of my life.

    Matt
  • Hi,

    I've had both. I'd never buy diesel again. I find no issues going into the mountains in Canada.
  • It’s worth noting that any Super Cs based on the class 5 trucks will have a de-tuned version of the light truck diesels. Still way more torque than any of the gassers, and no substantial power loss at altitude.
    Equally as handy is the exhaust brake. Gotta come down every hill you climb!
  • Go ask the question at a diesel repair shop. Repair shops have a lot more headaches and the drivers are not happy with the new diesel standards.

    I would be asking the professional truck drivers how they feel about the new emission standards for diesels before i bought another diesel.
    For what you need to do hauling that combined weight, i agree the new Ford gasser would be my choice.

    If you were hauling a heavier load commercially, then you would have no other choice than a diesel.
  • As with any question, the more specific the question, the better.

    For example, if your experience is towing with an older stock diesel in the 500-600ft-lb range and a 4 or 5 speed trans and potentially higher gearing (like an old 2nd Gen with 3.55s), then you will not be disappointed with, say, a new 7.3 Ford gasser. IMO.

    If you're towing now with a modern diesel or even a modded older one with some serious power, exhaust brake, 6 speed, etc, then I believe you'll absolutely notice the loss of power, especially at altitude where naturally aspirated engines get pretty asthmatic once you're up in the stratosphere.
  • Had 2 gas motorhomes prior to our MB Sprinter based Navion. The Roadtrek was a 2002 Chev 3500 Express van with a 5.7L V8, and it wasn't too bad except the engine was in the "doghouse" position between the front seats and dash, so noisy in the power band RPM range on uphills, and it threw some extra heat inside the cab in warmer weather. Fuel economy wasn't too bad, overall. Our Sunstar 26HE was on the F53 with the V10 3V 6SPD transmission. Same as the Roadtrek, only louder and hotter and harder to get to the seats around the doghouse. Fuel economy doesn't apply to the V10, because it's probably around 6-8 mpg average. That V10 screamed uphills when towing our Wrangler, again because the power band RPMs were at or above 4,000.
    Our Navion on the Sprinter 3500 cab chassis with the 3.0L turbocharged V6 diesel is better than both the gassers, in our opinion, and we get 15 mpg average, and 13 mpg towing. It's power band is typical diesel, 1400 rpms for peak torque, and around 3800 rpms for peak HP. It's a nice handling motorhome for it's size and weight, and it pulls our 4500lb Wrangler effortlessly.
    So, I'd stick with diesel, given the choice.