brake disc scrapeing ?

If the disc and pads have been replaced correctly, everything should be quiet, both in driving and braking. However, the disc is partially covered by a water splash guard which just may be rubbing on the disc, or maybe a suspension joint is a bit worn, doing the same thing. Can you be absolutely certain that the noise is coming from that wheel? I'd consider jacking the car up on that side, and spinning the wheel to see if the noise is still there.

John
April 2009