Any ideas on what I should look into? I can only hear it at low speed (5-10mph), coming from the rear, doesn't seem to be directly related to brakes at all although my rears need doing soon. Doesn't sound like a grinding metalic noise like I normally assocoate with a wheel bearing. I hear it when reversing off my drive and when casually driving along at slow speed. It kinda sounds like something from a rear shock? Are they known to squeek after a while? Could it be a bush?

When going over those small harsh speedbumps (the ones that are only like 10inches thick) not sure if you have them in the states, the rear end does squeek quite violently so i'm wondering if it's just getting worse.

I've checked my wheel nuts before anyone suggests it too!

The S is a 2005 on 60k miles.

 

I'm having the same issues, except mine are coming from front and back Mine sound like it's either the suspension or perhaps even the steering column. I haven't had a chance to look under the car just yet but it does get annoying especially when I'm going at slow speeds. Keep us updated if you find any possible solutions. Good luck!

 

Probably top mount bushings on the struts, spray them with some silicone spray the noise will probably go away.

They are probably a little dry, has happened to me before..

 

I was going to guess the sway bar bushings. That may also be the culprit (has made noise on some of my older cars).