My car makes a loud "grinding" sound which I'm 90% sure is coming from the A/C compressor. It goes rubrubrubrub at the same RPM as I think the compressor is spinning and comes from that area of the engine. It started softly, then got a lot louder. Now it seems to be silent when the car is running above about 2000 RPM's and after dropping to idle a few seconds it comes back, then disappears again on acceleration. Anyway, do all you A/C experts think the compressor is shot? Are there any parts of these things that can be repaired or replaced, or is the whole unit a goner? Oh, here's the kicker, the AC works fine. Doesn't cycle a lot, blows nice cold air, never shuts itself off, etc. What do you think?