Moaning rear wheel noise but only during during "sharp" turns.

What is your question?

I have a 2005 Pontiac Montana SV6 AWD that has a moaning, binding noise from the passenger rear wheel area, but only when I'm in a turn with the steering wheel rotated more than one full revolution in either direction. Nothing visible is rubbing or interfering with the wheel or tire. Vehicle has ABS, traction control, and an automatic load-leveling rear suspension. Any ideas what this might be????