I agree with phil-l. I'd strongly suggest that you rule out the power steering pump. This sounds a lot like how a bad pump sounds.
https://www.youtube.com/watch?v=BD3PTy2B1EI
You should be able to isolate the noise by checking each bearing with a stethoscope tool, or a hose with one end in your ear and the other pointed to the location.
You can get the effect of the stethoscope with a long socket extension or breaker bar (or any other convenient metal shaft). Put one end to your ear, the other end on the part. You can normally isolate bearing noise this way.