rxcrider was right. On my homeward commute tonight, I picked up a Mobil 1 M1-102 oil filter and a couple of liters for replacement. New filter didn't fix the noise, so further inspection found the rubber grommet (# 34321234629), holding the weight of the exhaust, working itself out of it's bracket. Apparently when new, it's held in by a circlip (# 07129934330), which is now missing. I reseated the grommet between the bracket and the exhaust holding arm. It was quiet around the block. Nice!
Originally Posted by rxcrider
I'm going to order both pieces tomorrow.