When did rust become a problem with 1990s Mercedes-Benz S-Class models?

I'm looking for a 1991-1999 W140 Mercedes-Benz S-Class. I've seen two 1997 models, both of which had rust problems around the wheel arches. Can you tell me in which year Mercedes-Benz started producing the S-Class with this problem, and am I safer with slightly earlier examples? I used to own a 1999 E300, and that had terrible rust.

Asked on 14 July 2010 by Clinteastwood01

Answered by Honest John
The problems seem to have started in about 2006, but the W140 was assembled in Thailand and in India as well as in Germany. The problem was treatment of the metal and the type of sealants applied. Early W220 S-Class cars can be really shocking, and that and multiple electrical problems are why they go for peanuts these days.
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