When the streering is tunrned and a quicen noise isheard what is the problem
the flat belt tensioner is worn. causing the belt to swim "crooked"...replace the belt and tensioner~ https://www.google.com/#q=2008+volvo+xc90+3.2+accessories+belt&tbm=s hop
How many miles? Look for power steering fluid turbulence inside reservoir. If it was a tensioner it would be a constant noise at idle.
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