Tire Sidewall problems of the 1998 Ford Expedition

Traveling on new portion of I-670 my rear tire blew out. SUV has 52,000 miles on it, the tire that blew was the original and it had 6,000 miles on it. Spare was put on SUV oct 30, 2003.

At 8:30 am on a cool morning, the tire suddenly exploded without any warning after only 3 miles on I-17, and a total of 16 miles from start up. The highway was dry and clean. I coasted to a stop without braking, or any steering problem. The outside side wall is completely seperated 3600from the tread. There are 25 radial splits in the sidewall, averaging 3" long, almost to the rim. The tread shows no damage. The inside sidewall has one damaged area near the tread. The tire was not hot. The other three tires appear to be ok, but so did this one prior to failure. I have photos, and will keep the tire for inspection. The tire was made in canada. Please advise if you want the tire or photos. (tiresize: p255/70r16)( dot number: tire size: p255/70r16 ).

2 tires suffered sidewall failures, 2 or more holes in sidewall, cool air temperature about 55 degrees f. Tires inflated to 35 psi, both failures on improved gravel/ dirt roads in alaska, both tires destroyed, no damage to vehicle. ( dot number: tire size: p265/70r17 ).

Sidewall of the passenger side front tire is coming apart. (tiresize: 26570r17)( dot number: tire size: 26570r17 ).