In both of my MB diesels (1980 240d and 1983 300d), I replaced the steering damper when I adjusted the play out of the steering. You can tell if it's bad by removing it and checking to see if it functions like a shock.

Both of the ones I removed had about 130 to 150 kmiles and they were completely gone (you could slide them in and out with little to no effort.

They are easy to change but you have to get under the car. Please take all the appropriate safety actions before you get under it.

thanks
Joe