Installed two new Bridgestone potenza pole position re 960as in July 2010(purchased from thetire rack),on my 2003 BMW 540I(at Bridgestone tire dealer).rear,275R1835.two months later while driving 40mph on a very well maintained road(lake shore drive, in Chicago),loud bang was herd from the back and got flat without running over any debris on the road.claimed through the seller(the tirerack),the tire was sent to the manufacturer for inspection(since the cut and the disintegration seemed consistent with material detect) but received a cold shoulder from them citing that the blown tire did not have a defect. The seller refused to honor my warranty(the tire was registered for that). What to do?

- Chicago, IL, USA