Tire Tread/belt problems of the 1998 Chevrolet Express

I noticed a continuous tire thump" and stopped the vehical and checked the tires. The left front tire had a flat spot in the center of the tread, about 2in x 1. 5 in. There were no other abnormatities. After traveling about 30 more miles the "thump" got alot more apparent and I heard a loud "clinking" noise. I stopped and inspected the tire and found the tread was separating from the tire over about a 12 in. Of length where the steel belt stops at the side wall. The tread was still intact. I beleive that if I had not stopped when I did that total seperation of the tread would have occured within the next mile or so. I have the tire if you need to inspect it and/or I can send you photos . (dot number: vn1181a098 tiresize: lt 245/ 75).

Air temperature 100 degrees fahrenheit, air pressure in tire checked at 80 psi cold, speed 60mph. This is the third tire of this size and make, made in canada. This one and other two had about 9 to 10 thousand miles on the road. Each suffered a tread separation. Others had odi#735190. (dot number: tpc 2012ms tiresize: 24575r16 e).

My wife was driving on the freeway bring her car pool home with six children. She heard a loud thumping sound occur all of a sudden. The tire did not burst but we lost a significant portion of the tread. We have had the tires replaced with goodyear tires. The same day this happened we heard these tires were also being investigated. We still have the tires in our possession. (dot number: vn11b1a307 tiresize: lt245/75r1).