I have a 2014 Ml350 and have experienced the same vibration on throttle. I put on new Michlin tires and aligned. Helped but it still is there. Just bought a brand new GLC300 and I’m getting a vibration. There is something with Mercedes design that I think they resignate and the natural frequency Of the steering column is achieved. I had the 2014 in three times and the new Glc300 twice (only 150 miles on it.At what speeds do you feel it? Could just be a wheel balancing issue?