Gas mileage E450

Desert Captain wrote:
"Probably in some cases the E450 could pull a hill in a taller gear than the E350."

Why? The E450 does not have more power than an E350, they both have the same motor and transmission. The E350 has 4:10 rear end and does not need the 4:56 that comes with the E450 {to handle the extra load}.

That's why the 350 will always be turning more slowly {as in burning less fuel}, than the 450. Also that same engine in the 350 will be pulling a couple of thousand pounds less {assuming both are loaded to their respective GVWR's}.

If you are going to be towing or loading heavy, as in near your GVWR, the extra payload (assuming there is any), of some 450's and lower rear end make a lot of sense but they come with a stiffer ride and less mileage. Many of the larger Class C's are so heavy to begin with due to slide(s), levelers etc. they may not have much remaining payload available right out of the showroom.

One thing to look for when shopping for an E350 is the 55 gallon {optional}, fuel tank that comes standard on the E450. IMHO: The standard 40 gallon tank on many 350's lacks sufficient range.


:C

I think you're quibbling here because that is pretty much my point. But as life is, it isn't always that simple. There very well could be a time when an equal weight E350 and E450 could be one gear apart on a hill, with the E450 turning slower. That hill could be pulled in 4th for example in E450 but not on the E350 due to the axle ratio. But as I said, after a complete trip, the total engine revolutions of the E350 is very likely to be lower. Certainly if the E350 was lighter or more sleek, that would contribute to lower total revs.