Depending on which side..
Passenger side, it goes into a disconnect, and then to the differential.
Drivers side, goes straight into the differential.
You can narrow it down, It does mean a bit of work, but could save you money in the long run.
Pull a CV axle out (passenger or driver), and insert a Gatorade cap (No I am not kidding) into the hole, and reassemble. Take it out for a drive and see if the noise is still present. The CV axle and end nut is NOT needed for bearing retention.
If it is, do the same thing on the other side. If it isnt, you have narrowed it down to the side at least, unless its in the differential itself.