Should I buy a motorhome with a gas or a diesel engine?
Good question. Not a simple answer. In general, I do not think one type is always better or worse, rather, I encourage buyers to consider size and weight. When you get into larger motor homes, which I define as more than 34 feet and certainly more than 36 feet, I tend to think in terms of diesel power. As motor homes reach those sizes, they need more torque or grunt than gas engines can achieve. The biggest advantages of diesels are their power, along with better mileage, and less complexity. The disadvantage comes when repair time rolls around. Anything diesel is heavier and costs much more to repair. Some folks also have very little tolerance for the smell of diesel fuel and filling at truck stops virtually guarantees diesel on the carpet. The normal life expectance of diesel engines is 500,000 miles, an irrelevance for most owners given how long motor homes are kept before being traded. The advantage of gas engines is their much lower cost, compared to diesels; they average $20,000
Diesel fuel has a higher energy density than gasoline. One gallon of diesel contains approximately 147,000 BTUs of energy, while a gallon of gasoline only has 125,000 BTUs. This means it takes more gasoline to equal the power output of diesel, making diesel engines more efficient per gallon of fuel burned. Also, because diesel engines use the more efficient direct fuel-injection method (fuel injected directly into cylinder) compared to the port fuel-injection setup in gas engines where gas is mixed with incoming air in the intake manifold, the diesel system has little wasted or unburned fuel. Of course variations exist of many kinds but from our experience with moving RVS all over the country for the past 15 Years we find that the average MPG of a diesel RV is 7.5 and that of a gas powered RV is 5.5. – See more at: http://www.autobossrv.com/diesel-coach-guide#sthash.zmR7k6e0.dpuf
