1991 NISSAN D21 Tires Problems

AROUND FIVE YEARS AGO, WE BOUGHT 4 NEW DOUGLAS ULTRA TRAC 2 TIRES FROM THE LOCAL WALMART. THE TRUCK WAS RETIRED FROM HIGHWAY USE SHORTLY AFTER AND THE TIRES HAVE LESS THAN A THOUSAND MILES USE ON THEM. THE TRUCK HAS BEEN IN LIGHT USE AROUND THE HOUSE TO MOVE MATERIALS AFTER, AND SEEN LESS THAN ONE HUNDRED MILES USE. SILVER CITY NEW MEXICO IS A RURAL AREA WITH NO SMOG AT AROUND 6 THOUSAND FEET. I HEARD A NOISE IN THE YARD, WENT TO INVESTIGATE AND FOUND THAT A REAR TIRE HAD BLOWN OUT ON THE INSIDE REAR. THE FAILURE HAD COME FROM THE BEAD OF THE TIRE, ON THE SHADED SIDE OF THE WHEEL. THERE WAS NO OTHER DAMAGE TO BE SEEN ON THE TIRE. ON EXAMINING THE TIRE BEFORE REMOVAL, I FOUND THAT THE RUBBER WAS SO DETERIORATED THAT I COULD TEAR IT, CHORD INCLUDED, WITH MY...