2006 ITASCA SUNCRUISER Trailer Hitches Problems

I HAVE A 2006, 39 FOOT ITASCA COACH THAT CAME WITH A VALLEY INDUSTRIES TRAILER HITCH. THIS HITCH IS RATED FOR A MAXIMUM PULL OF 5000 POUNDS AND A MAXIMUM TONGUE WEIGHT OF 500 POUNDS. WHILE THE HITCH IS NOW FOUR YEARS OLD, IT ONLY HAS BEEN USED FOR APPROXIMATELY 17,000 MILES TO HAUL MY GMC ENVOY. THE ENVOY WEIGHS APPROXIMATELY 4700 POUNDS AND THE TONGUE WEIGHT, WHICH IS THE WEIGHT OF MY BLUE OX TOW BAR, IS APPROXIMATELY 35 POUNDS. MOST OF THE MILEAGE USED WAS TRIPS BETWEEN MICHIGAN AND FLORIDA. NONE OF THE TOWING INVOLVED STEEP GRADES, SUDDEN STOPS OR TRAFFIC CRASHES. I ALSO HAVE ANY ACTIVE TOW VEHICLE BRAKING SYSTEM. PARTS OF MY HITCH ARE ACTUALLY MISSING. RATHER THAN BENDING, THE METAL SIMPLY BROKE APART. FYI, WINNEBAGO/ITASCA REPORTEDLY NO LONGER USES VALLEY INDUSTRY HITCHES. AS YOU CAN SEE FROM THE PICTURES INCLUDED IN THIS E-MAIL, THIS VALLEY...