1983 ELDORADO MONARCH Tirestreadbelt Problems

ON AUGUST 20TH 2007 WHILE TRAVELING AT 60 MPH IN A 27 FOOT MOTORHOME, THE RIGHT FRONT TIRE EXPLODED. IT WAS A GENERAL AMERI 550 MS 235/85/R16. THIS TIRE WAS 90 % NEW WITH NO WEATHER CHECKS, BULGES OR ANY DAMAGE. IT WAS INFLATED TO 70LBS. I HAVE NEVER HAD THIS HAPPEN BEFORE AND I RUN A SCHOOL BUS FLEET AND DRIVE A LOT. I HAD IT REPLACED WITH A GENERAL AMERI TRAC. THEN, ON SEPT 30, 2007 AT ABOUT 8:00 P.M. ON I-75 BY GAYLORD, MI. AT ABOUT 65 MPH. THE RIGHT REAR INSIDE DUAL BLEW APART GIVING SEVERAL PEOPLE SOME FRIGHTFUL MOMENTS. IN BOTH CASES, THE TREAD SEPARATED FROM THE BELTS AND THE TIRE BLEW APART. I AM NOW CONCERNED ABOUT THE REMAINING TIRES. ALTHOUGH THEY LOOK TO BE IN EXCELLENT SHAPE, SO DID THE ONES THAT BLEW APART. I CONTACTED GENERAL TIRE TO SEE IF THERE WAS...