DRIVING WITH A TRAVEL TRAILER IN TOW IN I-81 IN NY ON 6/15/16 WE SUDDENLY HAD EXTREME SWAY. MY CAR/TRAILER HAD VERY GOOD HITCH/ANTI-SWAY DEVICES. WITHOUT MUCH NOTICE, I LOST CONTROL. I BELIEVE THE FRAME SUPPORTING THE HITCH RECEIVER FAILED CAUSING A BAD ACCIDENT RESULTING IN TOTAL LOSS OF OUR TOW VEHICLE AND OUR AIRSTREAM 25 FOOT TRAVEL TRAILER. I AM A VERY EXPERIENCED DRIVER WITH THIS COMBINATION OF TOW VEHICLE, TRAVEL TRAILER, AND HITCH CONFIGURATION. THE ONSET AND MAGNITUDE OF THE SWAY (VIOLENT) CAUSED ME TO LOSE CONTROL AS WE WERE GOING 65 MPH ON THE INTERSTATE HIGHWAY. I HAVE TOWED THIS SAME CONFIGURATION FOR TENS OF THOUSANDS OF MILES WITH NO INSTANCES OF PROBLEMS. SOMETHING DRASTIC HAPPENED! I WAS PASSING A SLOW MOVING CAR , SO WAS IN THE RIGHT LANE HEADING SOUTH WHEN I STARTED TO SWAY. I REACHED FOR THE BRAKE CONTROLLER IN AN ATTEMPT TO APPLY THE TRAILER BRAKES. THE SWAY DRASTICALLY ACCELERATED TO THE EXTENT I WAS UNABLE TO REACH THE BRAKE CONTROLLER DUE TO THE VIOLENT MOTION. WITHIN A FEW SECONDS, MY VEHICLE CAME TO REST AGAINST THE GUARDRAIL ON THE RIGHT SIDE OF THE HIGHWAY (HEADING NORTH) WITH THE TRAILER JACKNIFED/PERPENDICULAR TO THE GUARDRAIL SUCH THAT I WAS BLOCKING BOTH LANES OF THE HIGHWAY. I EXAMINED THE HITCH AND TRAILER COUPLING AND ALL SEEMED NORMAL EXCEPT FOR DAMAGE FROM THE CRASH. THE HITCH FRAME OF THE SUBURBAN WAS TORN AND TOTALLY RIPPED FROM THE VEHICLE ON ONE SIDE.