not to be disagreeable but the mercedes suspension is set up with a lot of castor. this means the pivot point (like the pivot point on a bicycle) is angled away from vertical. the top is laid back like a bicycle. maybe about 7 degrees. this causes a lot of stability on roads like interstate. the car will want to go straight. on a crowned road it will pull and you will have to always steeer uphil.

american cars typically (especially suburbans) have almost no castor. they deal with the car going straight by putting mechanisms in the power steering system that pull the steering back to center. this works ok but you won't have any "feel" for what the road is doing. the drawback is if you get some wear or the tie rod ends are adjusted a little wrong the mechanism will pull the car to one side or the other without regard to exterior factors, such as the crown in the road.

for myself i like this mechanism because if you happen to wander to the wrong side of the road in a benz you can feel it in the pull of the steerng wheel.

race cars are set up this way too.

this casor also will make the steering come back to center on the other side of a curve if you just let go of the wheel.

sounds like yours is behaving normal for a benz.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.