-Check your front springs. Sometimes the rubber, isolation thing around the spring where it meets the shock strut can move out of place, in which case you have metal on metal noise when you go over a bump. I doubt the dealer removed the springs/strut to find out if that were the case, but it could be simply something that wasn't tightened enough.
It's likely somewhere in the suspension, but I would try and rule out anything stupid, like a loose panel or something. Did the dealer hear the noise you mention?
__________________
[09][MB][6-Spd MT][Touring][Stillen Gen III][K&N][Borla CBE][Evo-R]
|