Originally Posted by Ottawa John

I had this happen too. And as odd as I thought that it was, it was explained to me this way by a very knowledgeable mechanic - " Why would you think that it's odd? They're all made at the same time in the same factory with the same materials and the same tools. They're put in the same car at the same time and operate under the same conditions for the same length of time." I thought, well, duhhh. The technology and materials today really does standardize things much more than it did in the past, and this isn't uncommon at all. When one goes the other won't be far behind.
Replace them both and don't worry.