Everyone seems to like the fuel economy and perhaps quietness (depends on what models one is comparing) of a diesel but what about the initial cost? Every diesel based Class C (eg. Winnebago View or Fuse) is $30 to $40 thousand more than a comparable Ford E350/E450 based motorhome. You can certainly buy a lot of gas for that price difference. Not everyone wants to pay over $100,000 for a motorhome. That's why Ford still sells many thousands of the E350/E450 cutaway chassis to the RV industry each year.