[acpd22]

I know these cars are small and therefore will have more vibration than a much larger vehicle. But I have a vibration at 62-67 MPH that causes the passenger seat to shake violently. It doesn't do it if someone is sitting in the seat. Any suggestions? 2013 Smart Passion. Just put on new rear tires today.

 

[misfitsailor]

My first thought would be to have the shop double-check that they actually balanced the tires. If your road is smooth, the ride should be smooth.

 

[jimvw57]

double check tire pressures, and maybe tires for a bad belt, or make sure rims are properly on the car and not crooked

 

[smark]

Tires is out of balance. Could have lost a balance weight, after driving. Take it back to the tire store, to have them check it out.

Also check out your lug bolts. Make sure their on tight, and Torqued to the right specification. After a tire rotation. We’ve had a couple our vehicles, after a week driving. The Lug nuts came loose. On the highway. Had to be retighten, and torque.

 

[kjp4756]

I had the exact same problem...same speeds and everything. It's a wheel balance issue. In my case both front wheels were warped...not bent but warped. No idea how that could happen but it was like that since I got the car. I ended up getting 2 new steel wheels for the back and moved the old backs to the front. Nice and smooth now.