Tire Valve problems of the 1999 Ford Windstar

Traveling at approximately 65 mph when left rear tire near instantly deflated causing total tire failure before the vehicle could be pulled to side of road. Tire sidewall was totally destroyed. Spare installed. No punctures, tears or cuts were found anywhere on the tire tread or sidewall. The only known cause of the tire failure was a cracked (cut) valve stem in the area where the stem seats against the aluminum wheel allowing air to exhaust quickly from the tire once the crack propagated to inside. Phoned the dealership where the four new replacement tires were installed 3 years, 7 months and 23,170 miles prior to discuss the blowout issue. It was mentioned that this is the 4th tire out of 8 that I had purchased from them (three on my other vehicle and one on this vehicle) where I had tire failure due to cracked valve stems. Reference odi #s 10254187, 10254189 and 10254191). Cracked valve stem information; tr 413, 217 eha, germany, 03. To date, the tire and valve stem have not been replaced and are being saved for reference.