OK, here is the complete story. I went to the dealer to have an alignment. They replaced tie rod (right side), idler arm and steering shock. They also told me that everything is fine at the rear end. When I picked up my car it felt so good, very tight. But after few miles, what the h*, it was pulling right and very hard! Also the ride was affected strongly by road crown and at the same time steering felt very loose. But after paying the dealers bill I wouldnīt want to go back to them!
I decided to find an indy alignment specialist. Well I found very reputable one with high-tech alignment rack (they do also MB:s) and let them do the alignment without saying anything what dealer has done previously. Got my car back, they told me only small adjustments were necessary. There was NO improvement in ride quality after this second alignment!
Then I heard about experienced MB tech who runs his own shop. Well this was the key to everything! Went to his shop and he found that tie rod (left side) and upper control arms are shot. And what about rear end? He shifted the shift lever when car was idling and told me there is something wrong at the rear end. On lift the subframe bushing on right side was found collapsed and outer trailing arm bushings were also found shot.. Later all worn out parts were replaced including 4 trailing arm bushings and diff. mount.
All this happened in a 1000 km! Lower ball joints, inner bushings of lower control arms still need to be replaced (to make sure). Maybe subframe bushings at front end also (?). And an alignment! And I thought all was fine under my MB at the first place. Just wanted to make sure everything is fine.. Good but expensive lessons were learned: donīt let anyone who is not experienced with MB:s touch your MB (except you of course). It is not THAT easy to work with them, one has to be interested in to work with them.
By the way, I strongly recommend this procedure to every 126 owner (if not done yet), also do the trailing arm bushings:
My MB feels now very tight and it just WANTS to go faster everytime I am on the open road!