Yes the car uses dextron III atf... Make sure you get a new filter and gasket.
Personally I would go with a synthetic ATF like Royal Purple, Redline etc...

As far as oil grade, some people claim that changes in seasons require different grades. I've run 10w30 in all my mb's with over half a million miles of no problems (that were oil related at least).
Once again, I prefer synthetic, but that is a whole other can of worms that has been discussed to death.

George

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George Androulakis

Former Mb's:

1990 500sl R129 - 76k Original Miles - New project - Follow the saga http://90r129.blogspot.com/
1990 190E 2.6 148k mi (sold)
1989 420 SEL 246k mi (sold)
1995 C220 175k mi (sold)
1992 190e 2.6 74k original miles (sold)
2000 c230 Kompressor 122k miles (RIP)
1996 C220 149k mi (sold)
2000 C230 Kompressor Sport 127k (sold)

Current Cars:

2009 Mercedes c300 4matic
2006 Mercedes s430
2005 Jaguar XJR
2003 Cadillac Escalade