Low frequency whining noise, Rear shaft drive bearing failure?
 

I think I'm hearing a low frequency whine noise in my 2009 RDX AWD, 64k with the pitch increasing as the speed increases, but still not a high pitch. I say "I think" I'm hearing the sound because it is so benign and sometimes I think it might just be road noise, but over the last month or so it seems to be more noticeable. No whining noise when idling at a stop, and shifting to neutral while driving doesn't eliminate the noise. I think it may be the rear shaft drive bearings, and if that's the case:

• I'm pretty good mechanically, (Brake jobs, starter replacement) so what is the difficulty level in replacing the rear drive shaft?
• What should I expect to pay for the part, and any suggestions as to where to purchase?
• If I can live with the noise for now, will the drive shaft fail without warning and leave me stranded?

I appreciate any advice that anyone can offer on this!

Are there any dyno shops in your area? It may be worth paying for an hour of time and being able to listen all around your vehicle while the wheels are turning to find out for sure where the noise is coming from.

Does it get louder when in either direction of left or right?

If it gets louder when you turn left, it will be a right wheel bearing. If it gets louder when you turn right, it will be the left wheel bearing.

Yep, it was the front driver's side wheel bearing. Thanks for your help!