DRIVING 45 MPH (SPEED LIMIT) ON DRY PAVEMENT, OUTSIDE TEMPERATURE 80 DEGREES FAHRENHEIT. LEFT SIDE FRONT BRIDGESTONE DUELER HT 684 II 265/65R17 110S TIRE SIDEWALL COMPLETELY SEPARATED FROM TIRE, REMAINDER OF TIRE BLEW OUT WITHOUT WARNING SIGNS AND BLOWOUT CAUSED EXTENSIVE DAMAGE TO FRONT OF 2008 TOYOTA 4RUNNER SR5, BLEW ENTIRE FRONT BUMPER OFF VEHICLE. DAMAGE ESTIMATE IS NOT YET IN. THIS OCCURRED MAY 2, 2012. ON OCTOBER 13, 2011, RIGHT FRONT DUELER HT II 265/65R17 110S TIRE BLEW ON WET ROADS, VEHICLE DAMAGED OVER $14,000.00 COVERED BY GEICO INSURANCE. INSURANCE WILL NOT COVER THIS INCIDENT BECAUSE VEHICLE WAS LOANED TO DRIVER NOT AUTHORIZED BY MY AMICA INSURANCE POLICY. POLICE REPORTS STATE MECHANICAL FAILURE ON BOTH INCIDENTS. STILL HAVE TWO MORE OF SAME TIRE ON REAR.