I have put the sub pans on with a new gasket but no sealer and it seems like they leak every time. Unless the two mating surfaces are PERFECT, the gasket inevitably does not seal properly. The only way to have PERFECT mating surfaces is to have two brand new components. I always use a thin layer of Mercedes 5900 sealant, part number 003 989 98 20-10 for insurance purposes. I hate doing things twice, especially when it is customer pay. Mercedes doesn't even use gaskets on the new stuff, just 5900 sealer. You might want to change the o-rings for the oil level sender while you have the pan off. The o-ring part numbers are 017 997 57 48 (1) and 017 997 58 48 (1). The sender connector goes through the block and is held on by a clip. Very easy to chabge the o-rings and worth the effort.

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Cars:
1993 400E
1993 300TE Wagon
1985 300D Turbodiesel w/ 688,000 Miles On Original Eng/Trans
1979 300SD
1977 Euro 6.9
1967 230S IMA Universal Wagon
100 Or So Parts Cars

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