I have some tonque-in-cheek/FWIW comments with respect to several points in posts above:
- The Chevy option for a Class C may cost more, but that in no way makes it an "upgrade" when buying new. It appears to me that it's a market competitiveness issue for Chevy.
- Regarding Chevy chassis Class C stability in crosswinds ... what is the 4500's lateral rear width measured to the outside of it's duals as compared to the same dimension for a Ford E450? (As a side note, the E450's rear width is wider than the E350's rear stance.)
- Many Ford V10 engines go to 300,000 miles and beyond in delivery, ambulance, etc. service.
- The V10 is a higher revving engine than the Chevy 7.4. Maybe that's one of the reasons that the E450 has the aggressive rear differential ratio that it does - to make sure that one can get the V10 into it's highest horsepower output range.
- I believe that the V10 was designed to provide a fairly broad and flat curve of torque versus RPM. This may have been to provide consistent lugging torque for truck use at all horsepower output levels, which of course are RPM dependent. How do the Vortex curves compare - more peaky or about as flat?
- I use oversize tires on my Class C to get it's top gearing overall ratio up there for improved gas mileage (and ground clearance). I could go even larger on tire diameter - since the fender wells and suspension allow it - but don't, so that the DW can still get up into the cab. Since my small Class C under-loads the E450's GVWR so much, the larger tires' negating some of the rear differential's aggressive 4:56 ratio advantage does not cause any noticeable pulling power problem.
- My E450 Class C needs no rebuilding of anything for it to drive like it does ... "like a van". Ford's Twin I-Beam front suspension must have something going for it or they wouldn't have stuck with it for so long. I'd like for once for someone to offer a clear, accurate, and short defense explanation of the advantages of Twin I-Beam suspension in a light/medium-duty truck chassis. All I read is Twin I-Bean bashing from folks who offer no engineering perspectives supporting their bashing. My old 1965 Ford Ultra-HD 3/4 ton pickup even had Twin I-Beam front suspension and I would carry, in our mountains, up to 6,000 lbs. of rock in it's bed with narry a handling problem.