Neither of those can cause a rumbling noise. Your car has struts on the front and rear. They are just like giant shock absorbers except they are the part that holds the wheels straight up and down. When they wear out, the car will bounce up and down more than normal over bumps in the road, and they can let a tire bounce like a basketball going down the road. If they get really bad, they can make a clunking noise too.
For a rumbling noise, the first suspect would be the wheel bearings. Your mechanic might use a tool called the "Chassis Ear" to find the source. That is a set of six microphones, a switch box, and head phones. He switches between the microphones that are placed near suspect points, and listens during a test drive.
Happy to hear you escaped Wisconsin. I hope to one day too.
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Sunday, July 17th, 2011 AT 9:33 PM
