In my experience, this issue cuts both ways. I see more and more new tires that are basically junk. Valve stems too. We have stacks of tires hauled off several times a year that have good tread depth, but are not round, are badly cupped, or have busted cords and look like a snake that's swallowed a rat.

There was a huge valve stem recall a few years ago. New import valve stems that would start to crumble within a year. I have dealt with many ruined tires because of failed valve stems that had been replaced with the new tires.

Other than old tires that were burnt up in the sun, I personally have not seen age by itself cause a tire to self destruct. I am not saying it cannot happen, just that I haven't personally experienced it. I have however, seen tons of newer tires with construction problems.

I go to the junk yards and get new take out spare tires from the wrecks to use on our trailers. They are mis-matched, so I don't want to run them on the cars. But they are new and cheap, and work well on the trailers. Some of these tires are 10 or 15 years old. We have done this for years with no problems to date.

To summarize, just because a tire is 10+ years old, does not mean it is junk. And just because it is new doesn't mean it is good.

Just my .