99 chevy malibu 4 cylinder

When it's coasting or idling, it's making a kind of oscillating squeaking noise about maybe 5hz, in time with the S-belt.

I thought it may have been the compressor but turning the AC on/off seemed to have no effect. I'm hoping it's not the alternator, because that was just rebuilt like a year ago (the repair place actually billed for a new alternator, and we had to bitch at them for lying about it). But I don't really know what else is connected to this belt, and i'm wondering a) what is it b) should I be worried

On an unrelated issue... I just got new tires (4) and an alignment done about 2 months ago, but my car kind of shakes (i would guess at approximately 10hz) more than I think it should at about 70+ mph. It was actually doing this before the new tires, but I thought my wheels were out of balance and alignment, but this doesn't appear to be the case. What else would cause this type of shaking? It happens whether i'm cruising or braking, so I don't think it's the brakes either.

[Edited on December 1, 2008 at 7:48 PM. Reason : ]

12/1/2008 7:48:12 PM

muffle bearings

12/1/2008 8:02:49 PM

These kinds of muffler bearings: http://www.urbandictionary.com/define.php?term=Muffler%20bearings

google- 1
Schnepelx- 0

[Edited on December 1, 2008 at 8:08 PM. Reason : ]

12/1/2008 8:07:20 PM

the fact that you had to look it up in urban dictionary is an automatic win for me actually

[Edited on December 1, 2008 at 8:54 PM. Reason : although the original spelling error by me might make it even lol]

12/1/2008 8:51:27 PM

^

12/1/2008 8:58:12 PM

Are you sure it's 5hz and not 7?

12/1/2008 9:29:45 PM