Gas or Diesel: Which is the Frugal RV Option?

The following article was written exclusively for frugal-rv-travel.com as a guest post.

When it comes to travelling frugally in an RV the question often arises: gas or diesel? This is the age old RV question that has sparked many a discussion (and argument). If there were a straight forward answer this question would have been settled long ago. But the truth is that it depends on your travel habits. Read on to learn the differences between these two engine types and figure out which is the most frugal for you.

The Fuels

Before we get into the differences between gas and diesel engines, we need to learn how the fuels that run them differ.

Diesel is a fuel oil that has a strong smell and leaves a stain. Diesel is a non volatile fuel, which means that it can be stored for long periods of time without evaporating and its vapors are not flammable.
Gasoline is a blend of hydrocarbons, and takes more energy to produce than diesel. Gasoline is flammable, has a strong smell, and cannot be stored for a long time as it evaporates. Gasoline has a higher combustion temperature than diesel.

The Engines

Next, we need to learn how the two different engines utilize the fuels to power a vehicle.

Diesel engines work by atomizing the fuel and injecting it into the cylinder along with air. The air and fuel are compressed to the point where they combust and push the piston. Diesel engines do not need a spark to ignite the fuel.
Gasoline engines work by injecting air and fuel into the cylinder, compressing it, and igniting the mixture in order to push the piston.

Now that we know how each engine works at the basic level, we can discuss the operational differences between the two.

A diesel engine has lower RPMs with more torque (towing power, basically) than a gasoline engine. Diesel engines are also more fuel efficient and typically last at least twice as long as gasoline engines with proper maintenance. These engines also do not lose horsepower with elevation. However, they are more finicky and need to be finely tuned to function properly. Also, cold weather can cause problems in diesel engines including longer warm-up times and thickening of fuel, which necessitates using fuel additives. Diesel fuels are also louder and give off a stronger smell than gasoline engines. Technology has been implemented in modern diesel engines to alleviate these downsides; however, it does add complexity to the engine and increase the cost.
Gasoline engines have higher RPMs, require less precise tuning, and are easier to service compared to diesel engines. Gasoline engines run better in cold weather, are cheaper to build, and the fuel is almost always cheaper and more available. The downsides are that gasoline engines have less towing power, the engines do not last as long, and they have lower fuel efficiency due to heat loss. Gasoline engines also produce more CO2 (a greenhouse gas) emissions.

The RVs

Now that we have covered the differences between diesel and gasoline fuels and engines, we can compare the differences between diesel and gasoline powered recreational vehicles.

Diesel RVs offer a more floor plans, more towing capacity (with less effect on MPG), better gas mileage, higher resale value, and a longer lasting engine. They also feature a stronger chassis, which offers better crash protection and a smoother ride. However, these are offset by more expensive fuel prices (.30 to $1 more per gallon), a more expensive unit price, and more expensive maintenance (about double) costs.
Gasoline RVs are more common, meaning fuel and service stations are more plentiful. Gasoline RVs also avoid the issues with smell, noise, tuning, and cold weather that diesel engines have.

Conclusion

When you compare the two engine types, diesel only makes financial sense in specific use circumstances. These include:

You want an RV longer than 35 feet
You plan on owning the RV for several years and/or putting excessive miles on it
You need a lot of towing power

If one or all of these is true for you, a diesel RV may be the better value. This is not to say that you will not prefer a diesel RV to a gasoline model, it is just the costs only make sense in these cases. For most RVers, gasoline offers a more cost effective and user friendly option when it comes to traveling the country.

About the Author

Bill Weston is an avid adventurist and outdoorsman who loves hunting, fishing, hiking, camping, writing, and good conversation with new and interesting people. Bill blogs on the topics of the RV lifestyle and outdoor recreation for Lakeshore RV, a premier RV dealer.