[ZGuy]

Yup. A gasoline powered F350 (a typical tow vehicle for a family of 4) pulling a large fifth wheel will get around 4 miles a gallon (according to the owners I've talked to). A diesel F350 pulling the same load will get around 12. This is for the years I'm familiar with. I'd need someone to tell me if the numbers for the 2005 or 2006 models has remained the same.

[newgeezer]

Yup. A gasoline powered F350 (a typical tow vehicle for a family of 4) pulling a large fifth wheel will get around 4 miles a gallon (according to the owners I've talked to). A diesel F350 pulling the same load will get around 12.

(With all due respect,) That looks like 3X, not 4X.

Still, that's impressive. ;O)