Having picked up my wifes c230k yesterday and being a dutifull husband, I am reading the owners manual so I can explain everything to her. I got to the windshield washer system and found that MB reccomends that you add their magic elixur to the washer fluid. Does anyone actually do this and if so why? Does this have special properties for deutchenglass.
Just wondering.

Many people have added plain old "blue stuff" with good results.

I was wondering if it was some kind of Rain-X product or something similar. They advise putting it in with the blue stuff also. I use rain-x and don't use the wipers too much anyway . But I was just wondering what the function of the "S" was.
I am really impressed with the little things in the car. Adjustable ventilation in the center console - who would have thought.

Don't know about "S" material. Never heard of adding rain-x to washer fluid. Although I believe they (rain-x) do make a washer fluid under their own name.

The S concentrate is wonderful stuff. It contains a lot of alcohol and I have never seen a windshield washer fluid that even comes close to cleaning like S. Unfortunately, for those of us who use a polymer sealant instead of wax, S is about the best thing there is to remove the sealant.

Since I'll probably use Meguires 26 (wax) that should not be a problem. I was just curious as to what the purpose of the "S" was and apparently it is just a cleaning booster. So if I happen to be at the dealer and if I remember and if it is not outragiously priced, I will probably get some.
Thanks for the responses.