Tire Sidewall problems of the 2004 Chevrolet Colorado

Tire size 245/45r20 I purchased a set a 4 cooper discoverer h/t plus tires for my truck in 2022. I haven't driven a lot of miles on them due to the fact that I live on the island of oahu, in honolulu, hawaii and have a lot of thread life left. I noticed that the sidewalls on 2 of 4 tires are cracking and separating. I removed them from the vehicle due to the risk of tire blowout and injury in the event of an accident. I've emailed cooper tires for information and warranty resolution and have yet had a reply.

I was driving my 2004 Chevrolet Colorado z71 4x4 in the passing lane on rt. 460, when the rear passenger side tire ( general ameritec tr p265/75-150) blew out, the whole side blew out. I was barely able to keep the vehicle under control. The tire wrapped itself around the hub and I injured my back trying to get it off . This tire seems too light duty for a pick-up, the side walls are very, very thin. Anyway, this tire only had 7400 miles on it when it blew out and neither the manufacture, nor the dealer would replace it. I ended up paying for a new one myself. But, like I said, I don't think this is a suitable tire for this vehicle.

Tire blowout at a slow speed, defective plastic fasteners, vibration, shimming could be caused by faulty tires that have more than one crease on the sides.