2002 E320 At around 65-70 mph the sterring wheel starts to shake really bad. It does it for a little while then stops.

 

ususally when the tire need balancing you have this kind of problem where the wheel shake at around 60mph and if you go over or under the shaking goes away.
try getting them balanced and see if that work

 

Added to the above if your shocks are bad at certain harmonics the car will shake,also check the inner tread of the front tires for wear or cupping or tread separation.
ohlord

 

Ohlord is very on target about the "harmonics" of the E class front ends. If there is the slightest imbalance in these cars suspension the ride is compromised. The tires must be balanced properly,, and they should check the rims for roundness as well as the tire tread for road damage...unless they are new. Don't be adverse to having wheel weights on the outside as well as the inside of the rim. Check the brake rotors for any warpage and make sure that the tire installer does not over torque the lugs...this can cause warping. Remember, if it spins it can cause vibration. Good luck. Bob R

 

You've got me thinking again. You say the steering wheel shakes at 65-70 and then it goes away after a while? Is this after the car has been sitting overnight and then you get on the highway with the tires cold? What size and type of tires are on the car and how old are they? Could be a flat spotting or tread separation issue. My SL500 has 19" Toyos that take about 10 minutes to warm up and smooth out after sitting for a day or two.