I have a 2012 C300 and I've noticed that whenever I get to highway speeds the passenger seat begins to shake. It's not just a mild vibration either, you can see it shaking. What could be causing that?

Also, my steering wheel has a very slight vibration to it. I'm not sure if something is wrong or if I'm just used to Lexus LS-like NVH levels.

It was just inspected my the MB dealer and the car has less than 12k miles.

 

Tires need balanced or you may a bent run from potholes

 

Ejecto seato cuzz

 

Same thing happens to me. I believe my rear passenger rim was bent when I hot a pothole. I know its not an alignment bc I did that less than 4 weeks ago. Ill let you know by the weekend when I get the rim fixed if it solved the problem.

 

ya i need to check mine over to from a similar issue but i went over train tracks hard

 

My passenger seat shakes at high speed. I think it is her knees that cause it .

 

I'm at the dealer buying a new tire. The current tire has a huge gauge and bubble. Luckily I didn't crack the rim. I must admit, I did hit the pothole pretty hard. I was actually thinking that in another 10 seconds my pressure sensor would go off and tell me I had no air, but it didn't, so I kept going! So yea....new tire expense coming down my ally.