Hello everyone,

On my C300, I have some stains or corrosion on the grill chrome piece and the door chrome trim as shown below.

The first two pictures are of my twin spoke chrome grill. The stains appear blue or purpleish relative to the chrome and is something I can't seem to catch on my fingernail.

The last picture is of my door chrome trim and it is this light white etching into the chrome, also can't catch it with my fingernail.

I'm curious to see if anyone else has encountered this issue before and what the best way to remove it is.

I did already try vinegar and a towel, but it does not come off.

Look like water spots which would be calcium or other mineral in water that was left behind when it dried.

Wash and then dry real well...
Then maybe Try a cleaner wax first...
If that does not work then maybe try a little vinegar on a rag to dissolve or soften minerals up... (test in hidden area first)

Also is that a plated plastic or metal part?

If plastic be careful and less elbow grease.

Can't tell from the photo for sure, but the door trim is likely anodized aluminum. Be careful. You can scrub off the anodization and then the aluminum will begin to blacken. As .y_gmn mentioned, try some vinegar on a q tip.

Had the same spotting. Dealer replaced it all under warranty.

It is certainly a plated plastic. Vinegar did not help much or at all, unfortunately.

I did order some Meguirs Wax Cleaner to try and clean it up. I'll report back.

That's interesting, so the door trim material is actually aluminum instead of being a plated plastic part?

I was watching this video where this E Class has a very similar but more severe issue on their trim pieces. They buffed it out with a light polishing compound. It seems to work.

What do you think?

UPDATE: The Meguiar's Cleaner Wax worked!

I tested a small area on the chrome grill with a cotton swab + cleaner wax. It seemed to work in the test area, so I went ahead and applied a small amount and spread it across the grill part with a microfiber. The discoloring/corrosion came right off with a little bit of elbow grease. I wiped it off again with a clean area, per the directions on the bottle. I made sure to rub very lightly and avoid any of the other plastic parts. The results were excellent, looks almost brand new except for the rock chips.

I ended up polishing the Mercedes start on the front and on the trunk while I was at it and I am very happy with the results.





Unfortunately, the white mark on the chrome door trim doesn't seem to respond to cleaner wax. I'm open to any suggestions, but I might let it go since its a small area. Gotta take the victories as they come.

There ya go.... only use cleaner wax sparingly...

Now cover that chrome with some wax or sealant or polymer or ceramic.... to protect it from spotting again..

And yes vinegar can take a bunch of applications or elbow grease since it is a weak acid....
Soaking and works but if the cleaner wax worked for you... awesome...

NExt time after washing dry car....