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Q: Thrumming and vibration under feet when driving

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Last week I noticed that my car started to have a thrumming noise and a vibration under my feet when driving over the speed of about 20 mph. It's a constant noise that doesn't speed up or slow down when driving. I just had maintenance done as well as a tire rotation and the dealership didn't say anything about having anything wrong with the car but the vibration still persists. It tends to stop when I break to a slower speed of about 15-0 mph. A better way to describe the noise I am hearing is you know when a Harley motorcycle passes your car and you get this vibration and sound? That's what it feels and sounds like. It's when I first noticed it thinking there was a motorcycle driving near by only to find out there was not one in sight.

My car has 31000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. The noise and vi...

Hi, thanks for writing in. The noise and vibration you sense could be engine vibration passing direction directly into the body of the car. This normally should not occur, but it can happen when engine mounts or a transmission mount get weak or fail. The engine can shift when it’s under a load, and some part of the engine or exhaust touch the chassis of the car - the chassis actually amplifies the vibrations - sounds and feels as though "something" is coming through the floor. I would recommend having YourMechanic.com perform a "Car is making a noise" inspection to diagnose these symptoms, and estimate the cost of repairs. YourMechanic.com can dispatch a mobile, professional mechanic to your location for diagnosis and repairs.

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