Greasy rocker panels at hinges - W204 Sport



After a rainstorm, or even a car wash, the rocker panels on my car get streaked with dark grease dripping straight down from the location of the door hinges. If my car was a darker color it wouldn't be quote so noticeable but it stands out on the relatively light Palladium Silver. When I open the door to examine the hinges I don't notice any particularly dark grease on them, either visually or by touch. Hence it may not be coming from the hinges but from somewhere within the doors. I'll check later today to confirm.
Is this typical? Is it related to some sort of factory-applied protectant, similar to cosmoline? Does it go away with time (my car has only a hair over 10K miles so still pretty new)? If anyone else has experienced similar, how did you treat it - besides regular washings or removal with a quick detailing spray?
Thanks for any and all suggestions.
Anyway, just clean it off from time to time if it bugs you. Comes off easy.



I was just wondering whether it was something I could displace with something else that's a little less noticeable when it runs, like WD-40, PB Blaster or white lithium grease. Just another of the many joys of ownership!




