Tire Tread/belt problems of the 2002 GMC Sierra

I have a 2002 GMC Sierra 1500 extended cab truck with firestone wilderness at tires which came with the vehicle. About 12:15 am I was driving eastbound on I-70 just west of junction city when I heard a loud sound from the rear of my truck, and was barely able to maintain control. At this point it was about 85ã‚â°f, but for a good part of the day I had been driving in 100+ã‚â°f heat (since about 5 pm, with a break in driving from about 8:30 pm to 10:30 pm). I pulled over, and found that the treads from my left rear tire had completely separated from the sidewall. I put the spare tire on and drove the rest of the way home (about 150 miles). Right now my tire is in 3 pieces: 2 sidewalls still on the rim, and the tread is a separate piece, still in a complete circle. Fortunately I think the damage is limited to the tire (which means I'm going to have to replace all 4 tires), and possibly the rim of the one tire. Right now I have all the parts, and will try and keep them when I have the tires replaced.

Firestone wilderness at 265 75 r16 treadbelt came completely off while driving. Ties only have 31xxx on them. Tire have been rotated every 5000 miles and infalted to manufactures specs. I will take pictures tonight of the damage and tire.

A firestone steeltex at (245-75 r16 lr e) mounted on the lr of my 2002 GMC Sierra 2500hd failed while driving on hiway 58 in the vicinity of tehachepi CA at approx 1630 hrs. The tread separated from the sidewall/body of the tire exposing steelbelts. The tread was not recoverable. The failed tire did not explode or disintegrate and remained inflated. The tire had accumulated 32650 miles since new (oem tire) without incident. All four tires were inflated to 75psi at 0630 am that morning in vacaville CA, and checked in bakerfield during a fuel stop. All tires were within 1 lb of another and registered 84 psi (warm inflation pressure). Contact with firestone indicated that the tire should be inspected by firestone engineers to determine the cause of the failure. The tire was shipped in accordance with their instructions. Firestone engineers concluded that the tire was "operated for a period of time at a pressure insufficient for the load being carried". The load on the tire was estimated not to exceed 2500 lbs. The failed tire retained nearly 70 psi when checked immediately after the failure despite a small leak from the separation. The tire was not damaged by road hazards or otherwise subjected to neglect. All tires were routinely rotated at 7500 miles intervals and most recently rotated at 30000 miles. Firestone has been asked to provide scientific evidence to support their assertion that the tire was not defective but has failed to do so. I have retained all four tires and will provide them for independent inspection. I have made one final request for information regarding the method of inspection and the documentation of those results. I have heard nothing fromfirestone as of 26 Feb 04. The dealership on record as selling the vehicle/tires insisted without hesitation the tire failed due to a manufacturing defect.