We just purchased a 2013 a few weeks ago and are having the same vibration/shaking at high speeds (75 mph). We have had it at the dealer everyday since we bought it and they cannot figure out what is wrong with it. We have had road force balance, different tires, balances, rim switches and it is still there. They were going to replace it with a new car, but the one we drove did the exact same thing. We are going to take it to another dealer and see if the might not be able to rectify the problem. Honestly I am at my wits end!!!!!!