The 5th wheel will have a heavier and more complex frame, requiring more material. Also, I bet there's more wood, wallboard and and all that sort of stuff, too.
I have noticed that your average 5th wheel floor plan is loaded up with all sorts of cabinetry and such where the "upper deck" ends and the "lower deck" begins.
Just a few reasons. BTW a bedroom slide will add a lot of weight to the pin.
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2008 (or is it 2009?) Rockwood 8280SS - 2007 F-150
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