Mine is a class A. 2008 Four Winds Hurricane 33H. Ford F53 chassis, with the V10 engine, 33' in length. The F53 chassis's original frame ands about 3 feet short. You can see where the motorhome or chassis company added an extra 3' of frame. The additional frame is the same size as the rest of the frame. I will add a few pics of the bracing for the hitch.

http://drcraceproducts.com/motorhome.html They reinforced and installed my heavier duty hitch. Mine has a GCVR of 26,000 pounds. Motorhome weighs in a little under 16,000 pounds loaded and ready to tow without trailer. I have a 2004 Haulmark Edge 26' , that weighs a little under 10,000 pounds loaded and ready to tow. All together everything weighs a little under 26,000 pound on a certified tractor trailer scale. Front axle, rear axle and trailer axle weights are all within my limits. According to motorhome weigh sticker.

It tows and stops great. Fuel mileage sucks, 5.5 to 6.6 mpg loaded.