Volvo Repair: 04 S60R Steering Noise, wheel arch, power stering

Question
I just purchased a 2004 S60R with 75k miles.  There is a humming noise when turning the steering wheel all the way to the left or right (usually making a U-turn or parking).  I've been told it could just be the AWD.  Is this normal?  I haven't noticed any clunking or other noises associated with it.  Thanks!

Answer
maybe your power stering fluid is low  or  most the time the problem is tire are rubbing on wheel arch plastic trim behind the tire you can do much about that  there is fix installing shims on turn stops but you are reducing turnig radius  and turning radius on that model is anyway to short if you can live with that dont worry than