Personnaly, I would not use any oil additives. Just Mobil Delvac 1 oil in the engine and a half bottle of Redline Catalyst in the fuel every few tanks results in virtually no smoke at 300K miles for me.

__________________
Steve

1992 300CE Sportline Sophie
1990 300E Emma - in the family
1979 240D Josephine - sold, but not forgotten
2004 Pacifica AWD

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