When I drive my Model S, I feel a lot of erratic vibration when driving 70+ mph. It was a pre-owned vehicle, and it drove like that from day one. I had the tires balanced, but that didn't help. Tesla Service Center said the tires were out of round. Since they were fairly new tires, Michelin covered 3 out 4 under warranty. One of the tires tested out as being OK. It still vibrates pretty bad when I drive 70+ MPH. It drives fine if I drive under 65 MPH. Thought it could be bad wheels, but they said they look to be OK. Anyone else having this issue, or have experienced this issue?