I have a '94 E320 Cabriolet with 49,000 miles. My independant shop thinks I need a passenger side rear wheel bearing because of a noise they hear. I jacked it up and could detect no play at all in the wheel. The wheel does make a noise, but I think it could be tire noise. Is there a definitive test for a bad rear wheel bearing?

Thanks...

 

Raise the wheel and spin it as fast as you can by hand.If you can hear the noise then you know it is not tire on road noise and you need to do the bearings.
ohlord
alldatadiy.com has the diy also
http://www.mercedesshop.com/Wikka/W124RearWheelBearing

 

I spin the wheel (I tried both sides) and the only sound I get is a little friction from the brakes. No rumble or grind from the bearings.