Diesel RVs Versus Gas RVs

When it’s time to buy a motorhome, are you better off with a Gas RV or a Diesel RV? This article takes a quick overview of the Gas vs. Diesel RV debate. Again, some of the technical motor home details are left out, to make the Diesel RV versus Gas RV head-to-head a little easier to understand. Also, even though most of these points can apply to a Class B or Class C motorhome, they’re specifically addressing the diesel and gas differences for two similar Class A RVs.

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For the sake of this particular comparison, we’ll assume that both the diesel motorhome and gas motorhome are the same length, have the same options and equipment, and are driven the same way down the same roads.


Let’s start with the first question most people have… the fuel economy of a gas RV versus a diesel RV. Yes, diesel motorhomes are more fuel efficient than there gas-powered counterparts. If a diesel RV is getting about 10 miles per gallon, a similar gas RV will be getting 8 mpg. That being said, the days of diesel fuel being cheaper than gasoline are long gone and you will pay more per gallon for diesel over gas. The price difference will have to be taken into account when calculating the actual dollar per mile you’re spending. For example (and we’re just making up easy-to-use numbers here), if gas is selling for $4/gallon and you’re getting 8 mpg, your motorhome is costing 50 cents a mile. If diesel is selling for $5/gallon and you’re getting 10 mpg, your RV is still drinking fuel at the rate of 50 cents a mile. You’ll also have to remember that most diesel engines require DEF (diesel exhaust fluid) for exhaust emissions. DEF can sometimes be hard to locate, and it’s not cheap.

Motorhomes – Diesel Engines or Gasoline?

Power is also an important consideration for a lot of people trying to decide between gas RVs and Diesel RVs. It’s almost impossible to give a fair comparison between the two engines when you get down to nitty gritty details. In general though, a diesel engine runs at lower rpm’s than a gas motor so (again, in general, and not always) the lower wear and tear can result in a longer engine life. To balance that out though, another generality is that repairs to a diesel RV engine are typically more expensive than those to a gas RV engine. Also, qualified diesel shops and mechanics can be harder to find. For the do-it-yourselfer, there are some maintenance tasks you can do on a gas-powered RV, but most diesel-powered RV repairs and maintenance jobs are too complicated for untrained people.

The next thing to consider is convenience. After all, the goal of an RV life is to relax a little. Typically, when comparing gas vs. diesel, gas is everywhere you could possibly end up in your motorhome. While diesel is almost as popular, there are still places where you can’t find a pump. Many people find that diesel is a “messier” fuel to deal with compared to gasoline, as it tends to coat and stick to things. For example, stepping into a little bit of spilled gasoline won’t track as much gunk into your motorhome as stepping into a little bit of diesel. If you’re not the relaxed kind of RV traveller, and you want to get back on the road before all the vehicles you passed pass you again, then keep in mind that diesel pumps move fuel into your motorhome’s tanks about five times faster than gas pumps. As well, diesel tanks can be close to 10% bigger compared to similar gas RV’s so, combined with the extra mpg’s, you can travel further between fuel stops.

A couple more things to consider – they may be considered minor or major points, depending on the driver and passenger. In Class A RV’s, a gasoline engine will usually be placed in the front, and a diesel engine will be located in the back. The biggest difference this will make is noise in the driver’s area. A poorly soundproofed gas engine can make conversation while driving your RV impossible. The location of the front gasoline engine cover (the doghouse) can be inconvenient. Also, but not always, a front gasoline RV engine usually means the generator is in the rear where you sleep. A rear diesel RV engine typically results in a generator located near the front, away from the sleeping area.

As noted at the beginning of this article, these are all generalities. People who own diesel RV’s will say they’re great, as will those who drive gas RV’s. There really is no “wrong” choice, so make the choice that you feel most comfortable with and don’t sweat the details.