I just bought my 99 c230 its a nice car and my first mercedes. I had to replace the both lower control arms shocks and 4 coil springs. along with lower ball joints.

The car has 18" linsor rims on it. they came with the car. When i hit 50mph the steering wheel shakes left to right and the car vibrates. I thought it was the tires. I had them balanced and checked at 2 different shops. I have crawled under the car and checked all bushings no play in any of the connection points. I had the shop who did the balance look over everything and they said it was fine, but i cant figure out what it is and i cant drive the car on the highway. I am beginning to think it is the rims. i did a search and from what i have read it could be bearings but i have no noises just shaking.

thanks for your input.