i cant say about how long that tire lasts cause i never had them but i never heard a customer of ours say a bad thing about them. if i get 30-40k out of a set of all terrains i'm happy.
but this is strait from our service manual
Cups or scalloping appearing around the edge of the tread almost always indicate worn or damaged suspension parts. Adjustment of wheel alignment alone will seldom cure the problem. Any worn component that connects the wheel to the car can cause this condition. Worn components should be replaced with new ones. The worn tire should be balanced and moved to a different location on the car if the damage is not severe.
im not going to dispute that yours cupped despite your front end parts being in perfect shape although a ram with perfect front end components is a rarity. these front end parts are cheap these days and not being greasable is just stupid if you ask me but im just stating what i was taught and what i have seen working at a dodge dealership for two and a half years.
