2012 TIFFIN ALLEGRO Structure Problems

[XXX]--I WAS TOWING A VEHICLE BEHIND A TIFFIN MOTOR HOME. A TOW BAR ATTACHES THE TOWED VEHICLE TO THE MOTOR HOME TOW HITCH. THE TOW BAR BEGAN TO SAG WHILE DRIVING ON A HIGHWAY. THE TOW HITCH IS WELDED TO A TIFFIN INSTALLED FRAME, THAT IS WELDED TO THE VEHICLE CHASSIS. THE TIFFIN INSTALLED FRAME CRACKED AND SEPARATED, CAUSING THE HITCH AND TOW BAR TO SAG. THE TOW HITCH IS ATTACHED TO THE FRAME WITH THREE BOLTS ON EACH SIDE. THE CRACKS HAD EXTENDED PAST THE REAR BOLTS AND CENTER BOLTS ON EACH SIDE. HAD THE CRACKS CONTINUED TO THE THIRD BOLT, THE TOW HITCH, TOW BAR, SAFETY CABLES, AND TOWED VEHICLE WOULD HAVE SEPARATED FROM THE VEHICLE. THE BOLTS USED TO ATTACH THE HITCH TO THE FRAME WERE APPROXIMATELY 1/4" SMALLER THAN THE DIAMETER OF BOLT HOLES. THERE IS EVIDENCE OF FRICTION, HEAT, AND DISTORTION OF THE WASHERS. THE...