Cruising above 20, I'm getting a sound from the rear of the car like a wheel is out of balance. I've rotated the tires, and the sound stayed in the rear. The sound used to come and go, but is pretty much constant now. You can hear it with both the windows up and down. The sound becomes more noticeable if you're under very light acceleration. Hoping it's a wheel bearing, but it might be something in the rear end. The stock gears are whining pretty bad, so I think the 10 bolt might be on its way out. Any ideas or suggestions are welcome.

 

If it is a clunking type noise it could be rust on the brake rotors. My T/A had an odd clunking coming from the rear end especially in corners and it ended up being the brakes.

 

cupped tire??

 

Bad axle bearing?

 

I find wheel balance is more felt than heard as a vibration that shakes the car which can be pinpointed to speed ranges.

If you have a sound you can hear, its something else usually as long as you can inspect the tire and find noting physically wrong with it.

 

Same here! I have that same symptom (including a slight whine) in my 2000 Formula A4. I think it might be a wheel or axle bearing going out or maybe pitted axles.