AS ironic as it seems, the early climate control systems MB used were Chrysler units. What I have read and heard, is that in Germany and Europe in general, air conditioning is not considered a "basic" necessity. Their climate, I guess, doesn't get as humid as ours so there is really no need for A/C. So in the early days MB used Chrysler units. Now as far as how long they used them, I don't know. Only in America does "luxury" mean cruise control, power windows, automatic trans., air conditioning, etc. My chassis manuals for my car show an interior picture of one with a stick shift. In America there is no way a big "luxury" car would have a manual. So you will find most of the bits and pieces that do fail on these cars are the things that MB wasn't used to designing or building. Not that their transmissions fail, but the other "toys" tend to not be as reliable.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member