I know this issue has been hit a few times before, i have read up on what others have said. Unfortunately I have called the dealer and gave them my VIN and I think I am out of the 5/100K powertrain warranty. I bought my CTS used and i thought the noise was coming from the tires. I'm in the process of getting staggered 20's put on but I think I need to get this issue fixed first. Seems like this will be very costly coming from Cadillac since its not under warranty anymore. I am guessing it maybe the driver side bearing that the noise comes from because when i curve to the right the ride is quiet. For a diagnosis its $80, then for one replacement Cadillac told me over $400. Could anyone give me some advice or feedback.....don't want to put rims on and still have this irritating noise. Thanks in advance.