It's definitely a squeaky chirp. I felt like a little bird was following behind me through my entire ride. I think I'll try Margot's suggestion first, so I won't have to worry about putting everything back together.

And fortunately, I've got a quick-link so I can remove the chain and clean the plates as well. It does drive me crazy to not be able to get all the mud and stuff out of there during my usual cleanings.