Welcome to 2CarPros.
Have you checked the basics such as tire balance or for a bent rim? Also, make sure the tires are worn evenly. Cupping or shifted belts can cause a vibration.
Let me know. Also, let me know if the check engine light is on which may indicate something with a misfire you feel, and if there is anything you can think of, other than speed, that causes it or changes it.
Let me know.
Joe
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Saturday, July 27th, 2019 AT 6:58 PM