DRIVING ON 81 N (MILE MARKER 160) IN PA AT 7:10 AM WHEN FRONT PASSENGER TIRE BLOWS OUT. THIS CAUSED ME TO SWERVE ACROSS BOTH LANES COME BACK HIT THE GUARD RAIL. TRUCK FLIPS OVER ONTO GUARD RAIL, SLIDES FOR A WAYS ON GUARD RAIL, THEN ROLLS OVER AS IT DESCENDS A HILL. THE BLOWOUT WAS IN MY LANE (GAUGE IN PAVEMENT) WITHOUT ANY OBJECT IN THE ROAD. TIRE LOST PRESSURE INSTANTANEOUSLY. BOTH TOW DRIVER & INSURANCE ADJUSTER POINTED OUT TIRE AS CAUSE OF ACCIDENT. THE TIRE WAS A MICHELIN LTX M/S2 WITH 33000 MILES ON IT, BUT IT HAD A 70000 MILE WARRANTY. SHAPE & DIRECTION OF TEAR IN TIRE IS IN THE OPPOSITE DIRECTION OF THE TIRE ROTATION, SO I TAKE THIS AS ADDITIONAL EVIDENCE THAT I DIDN'T RUN OVER AN OBJECT IN THE ROAD. *TR