The only sealant(engine & drivetrain) approved by MBUSA for warranty work is LOCTITE 5900. ON "all" surfaces & applications!!
AS Benzmac said YOU must be careful around oil passages not to use "TOO" much! Have seen several damaged camshafts from other shops after doing a rear main seal & using excessive sealant! THIS sealant started out as industrial only and now EVERY new MB engine uses this on almost every surface "INSTEAD" of gaskets.

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