I just replaced the brake pads on my wife's S60T5's front two wheels. Everything seemed to go smoothly. I have done this once before without a problem.
When the work was all completed and I drove the car, there is a humming sound that is coming from the right front (passenger side) wheel. I do not hear the sound while accelerating or braking, only while coasting and driving at a steady speed. I've had my wife drive the car back and forth in front of me several times trying to pinpoint what it might be. I can say it is definitely coming from that front wheel. The new brake pads do not seem to be rubbing in an unusual way, there's no grinding, no squealing, no spongy braking, etc. All seems to work smoothly accept for this sound.
I want to present one thought that I have just to see if I might be right. Could the humming sound be cause by air in the brake lines? I bled the brakes, but may not have done as thorough a job as needed.
Other thoughts?

Thank you!

 

Air in the line would give you a spongy pedal fer sure.
Jack up that side and spin the wheel and listen. The backing plate could be rubbing slightly and also check the retaining spring on the pads to make sure it's positioned correctly.
Ed

 

Good idea! I will do that this afternoon and post what I find/hear/see. Thank you!

 

Did you ever figure this out? I have the exact same issue on 2006 S60. Replaced brake pads on front, and when finished I get a "buzzing" sound when applying brakes. It appears to come from a silver round thing (that is a technical term ) towards the front of the car.