I was specifically going to mention that it seemed worse on crowned roads. Well now when I bring it back to the dealer I can give them an idea.

I can check the valve cover myself and I know that is covered by the warranty. If CarMax doesn't cover the bushings (assuming that is the issue) I'll have to locate someone in the Chicago area for the repair. In the mean time is the only consequence increased tire wear?

Thanks for the great info guys!