Weird gridning noise
 

I have these weird griding noise coming from the back end of the vehicle when i start driving at higher speed - around 75K/H (47mph). I am not sure where is this coming from, but i am sure its coming from the back. I am guessing it might be coming from the wheel bearing, anyone ever have similar symtomns? And if it is the bearing, how much would it cost to replace it?

The car in question is a 2000 A4 1.8TQ

Thanks

RE: Weird gridning noise
 

i have the same noise about 5 sec. after i start the car...no idea

RE: Weird gridning noise
 

I have had to replace 3 of 4 wheel bearings, they all made a howling noise at speed. I'll chech my receipts to see what they ran to replace them, they were all covered by warranty, but i'll check the price.