More details: It is a new design. I replaced the old one this summer. There was oil outside of the cap then. The cap was toast, cracked and lousy. With the new cap, no oil outside until early January. Now I have oil. New cap is still in good condition. I am hoping that this cap has simply 'broken in' and needs 'adjustment' by bending the tabs a bit. It is not as tight as the one on my '92 -- which is tight enough that I can barely get it off unless engine is hot.
1986 300E Anthracite + ECodes + MB Mileage Award