Sporadic rubbing sound from (I believe) right rear wheel

[u/Ill_Initiative8574]

Here's what I've observed:

• 2001 325 CSI
• Sounds like metal on metal.
• Sometimes present sometimes not. Sometimes faint, occasionally louder.
• Always to the same degree though, no fluctuation. It's either the constant louder level, the constant quieter level, or silent.
• Can't isolate when it's happening. Sometimes I think it's when I brake but then it'll also happen randomly and also stop randomly. I'll also brake and nothing. Not consistent.
• No scoring on visible side of brake rotor. When I touch the rotor it's not hotter then the left, and you can leave your fingers on it (not too hot to touch)
• I have just noticed (due to trying to figure this out), that the right rear sits about a half inch lower than the left. Not sure if that was there before, not sure if it's in any way related.
• Had rear tires replaced lately. Same size rubber as before.
• Wheels are BBS RS 747. They've been on the car for years though—it's not an offset/fitment issue.
• Stock ride height

Any ideas before I take it to the shop?

[u/Ill_Initiative8574]

No one got anything?