E450 vs F53 chassis

[Fastfwd75]

I get 9.5 MPG going 65 and slightly above 11 MPG going 60 with my F250 and 3600# + gear trailer.

I expect to get less from a 6.8L engine but how much less and what are the big differences between class C and class A chassis? Same engine, transmission, ...

The goal would be to choose between an 2008-ish Winnebago Aspect or Adventurer

I assume that the Adventurer gets much worse MPG due to wind resistance vs more profiled class C. Seems like the ride quality should be the same. Worse than a Diesel but better than what I have now with the trailer pushing/pulling when on a highway where "holes/waves" are the same length as my truck or trailer.

Any good reason apart from more storage to go class A? Seems like Class C would be big enough for me, MPG would better and ride quality would be the same. Also easier to park a 26-30' than a 35+

[rockhillmanor]

Fastfwd75 wrote:
I get 9.5 MPG going 65 and slightly above 11 MPG going 60 with my F250 and 3600# + gear trailer...

E450 MH V-10 > 55mph is the speed that will net you higher gas mileage.

I tried keeping it at a steady 55 mph for a fairly long distance and it makes a BIG difference

[Golden_HVAC]

Hi,

As stated above, the van V10 is less HP and has a smaller radiator, the engine is closer to your feet, and GVWR and GCVWR is much less.

The F-53 the headers are below the floor level, so engine noise should be much less. Typically it will have a 5.12:1 rear axle ratio, so the engine will spin faster for any given road speed compared to the van front with 4.10:1 rear axle ratio. So the motorhome V10 spins faster, and is rated to tow much more - the GCVWR is much higher. I think the lightest F-53 chassis now is around 18,000 pounds GVWR. The GCVWR allows towing another 8,000 pounds if the RV is light enough and not pushing it's GVWR.

Fred.

[tatest]

MPG will depend more on frontal area, then to a lesser extent on weight, than it does on which chassis is used.

Aspect has about 86 sq ft frontal area, is going to be maybe 12,000 to 13,000 pounds when you get it loaded. Adventurer is about 108 sq ft frontal area, needing 25% more power to push through the air at the same speed. Depending on which one you choose, might be 18,000 to 24,000 pounds ready to go, needing 50% to 100% more power to climb any particular grade at the same speed as the lighter motorhome.

What you get should depend on what space you need, and how much stuff you need (want) to carry. I find a 30-foot C adequate for how I use it, if I were to go to an A I would probably even downsize to something like the Via (though I would prefer to find a real Euro-style integrale with no slideouts).

But only you can figure out what size house you want, and the size of the house is going to determine the chassis. The MPG is what it is.

[n7bsn]

Bare in mind the "modern" F53 chassis gets the 362HP 3-valve version of the 6.8L V10, while the E450 gets the 310Hp 2-valve version.

Basically all F series get the 3-valve (post 2004) and the E series always gets the 2-valve

[sch911]

The F450 is the Van chassis, the F53 is a Medium Duty Truck chassis. There is really no comparison in ride quality the Van wins every time. The 6.8 is a great engine and is even better on the F53 with the 362 HP variant. For us it's the F53 with way more stuff...