1998 Mercedes Benz C230

Noises problem
1998 Mercedes Benz C230 6 cyl Two Wheel Drive Automatic 86235 miles

On October 16, 2009, I stopped for Gas before heading for my oil change. When attempting to drive off, I heard a swishing sound like water and a loud rattling sound coming from the rear of the car. This continued for several minutes even after pulling over to see if there was a problem with the tires. It eventually stopped and I associated it with the gas pump as the pump released air before releasing gas. I have noticed a rattling sound when making left turns periodically but it eventually stops. I have no idea what this is and the shop who did my oil change said they cannot diagnos unless it is doing it when they drove it. I am just worried as I already may need the rear brakes serviced. I appreciate any feedback you can provide.
December 14, 2009.

Check out the related content below while we wait for the question to be answered by a professional mechanic.