Most "newer" (our 2003 Jayco does) RV's have weight label that is supposed (which is why I say "Go Weigh It!) to state what it's "as shipped" weight is. Ours is 11,300 with GVWR of 14,000. Ours is the bargain-basement rental-fleet entry-level no-slides not-much-else 31A (32-ft long) class C. We can pack heavy and have a few hundred pounds left over on both axles.
A friend has a Jayco 31SS and it's "as shipped" is about 1,000 pounds more. If we packed it like we pack ours we'd be over GVWR.
If you want to think of an RV as a slab-on-grade house, there's a flat metal frame that the flooring goes onto, the walls mount to, etc. Our slab/frame is steel. I think some of the newer ones have substituted aluminum, and my guess would be they pick up about 500 pounds by doing that.
NCRoamer and I experience the same kind of axle weights - Front Axle nearly at Capacity. That can only be done if the Wheelbase is long enough. Ours is 218" and some newer ones are at and over 220". Again, Weigh It! If the wheelbase isn't adequate, then the Front axle will be Light (poor steering and tracking) and the Rear axle will be overloaded. I've seen this again and again. Instead of proper load distribution, the RV builder tries to hang a "walk around queen bedroom" behind the rear axle of a shorter coach. They don't put the axle farther back because they want to hide the fender wells under something like cabinets or appliances.
We just got back from a 900-mile evacuation/vacation courtesy IRMA. Towed our Frontier pickup at about 4,000 pounds. We ran about 65 mph running combined weight right at 18,000. Had to drop out of Overdrive often on the grades around Atlanta, but the power was there and MPG just a pinch below 8.
There are Class C's that big that'll do your job. Just gather the specs, actual data, and compare. See if there's enough capacity for your Crew and your Stuff.
If God's Your Co-Pilot Move Over, jd
2003 Jayco Escapade 31A on 2002 Ford E450 V10 4R100 218" WB