My '97 E420 has 95K miles and have been having difficulty with a slight shimmy. Did the Hunter balancing, high speed balancing, new tires. indexed on wheels, and still a slight shimmy. I've heard that replacing the steering dampener could be a solution. Any comments? Can I do this myself? I have a floor jack and jack towers and I can replace brakes, rotors,etc..., but have never done steering or suspension work.