CSMHOG
Member
My 09 did this for a very short period of time. It was actually the rear pad vibrating. (The furthest rear most upper part) It stopped on its own, don't know why. On the 120 mile trip home it nearly drove me nuts. The person following me seen it from behind, otherwise I may not have known what it was. It just stopped. Go figure.
I think I would dig into this one a little more, good luck.