I know, very precise. It happens in sync with speed. Just replaced all 4 rims, with 4 different tires since the old ones were shot, hoping that would do it. so far, it's making the same noise. It happens regardless of what direction I am turning, and there is no discernible play in the wheels, so it seems like it isn't the wheel bearings, and it doesn't matter if the car is in gear or not. It's a 5 speed Quattro if that makes a difference. Any help would be appreciated, thanks.

 

What wheels did you get? Are they rubbing against the fenders or inside?

 

Still could be a bearing going bad, but not bad enough to be discernible as to the side that's failing.

 

Have any mechanics suggested that the rear drive shaft needs to be looked at? Could be a hanger bearing, or out of balance shaft as the noise is constant with speed-check it out and let us know as I am good with diagnostics if I see/hear/ride in a car, but online is abit harder!