My C63 is about 5 months old. Did not have rain so far and finally got some rain this week and while driving in the rain I noticed that the wipers shudder and squeak. I tried different speeds and in both light and heavy rain and same result.
I sprayed the windshield with the windshield washers in the car and noticed that the shudder and squeak is gone. After a few minutes it came back. I repeated the process and it temporarily was gone with the use of the windshield washers.

In summer (no rain conditions), I have used the windshield washers to clean the dust/dirt and it was fine. This is the first time I have noticed it.

It's rather disappointing to see this issue with a new car. Is it an issue with the wiper blades (5 months is too soon for replacement - it's not hard when I checked). I am going to take it to the dealership, but thought should post this to get the wisdom from the experts on this.

An orthogonal question - is the right and left wiper arm slightly different in design?
Regards and thank you.
-V

Mine does the same and I’ve tried cleaning the windscreen with window cleaner and pure alcohol with no success. Replaced wipers with Bosch ones and the judder and squeak was even worse. Replaced wipers again with original MB ones and problem is still present but not as bad.

Thank you for that link has useful info. I will first take it to the dealer to see what they say (since it's new and is under warranty). Will update the post after that.

MB can build a V8 biturbo beast, but cannot get the wiper down right.

This is such an annoying problem to have.

Lets do a class action lawsuit? I can't drive in the rain at nigh because can't see sh*t.. 2 dealers tried to fix it for 8+ times

I also have it on my 18 C63 and it is driving me crazy. Its like they bounce across the windshield. I did the same thing excessive cleaning of the blades themselves and of the windshield. Nothing seems to work. I don't even want to use them when it rains its so annoying.

I switched to the Rain-X blades and problem went away.

Link?

Saw this, may be a possible solution
https://mbworld.org/forums/glc-class...ing-issue.html

I don't have a link, but they were the RainX silicone ones from Costco. Had a b-of a time figuring out which ones would fit, but ended up taking the OEM ones off and bringing it into Costco to physically compare.

I think it's a combination of the factory glass coating and crappy wiper blade material.

Had this issue to some degree with both of my MB cars. The paint sealant applied at the factory is the culprit. The fix was to thoroughly clean the windshield glass with either solvent (denatured EtOH or MEK) or abrasive cleaner (bon ami or similar). Also, avoid getting spray wax on the windshield as some types may adhere and make the issue noticeably worse.
If you like to use auto car washes and the problem returns, just give the windshield a good scrubbing with denatured alcohol and all will be well again.

WARNING!!! Do not let any solvents touch your plastic trim pieces. They may discolor them.