85 DSEL, MB dealers sell the oil filter housing wrench with a male hex head to accept a socket wrench. As you have probably discoverd by now the oil filter housing is between the back of the engine and the firewall.

It's easier to suction the old oil out through the dipstick tube than draining it from the oil pan drain hole. That's how the MB dealers do it. Consider purchasing a Griot's Garage oil/liquid extractor. I have been using one for 12 years, and it simplifies oil changes.

As for oil I use Mobil 1 15W50 in our 1995 E320. A changeover to synthetic oil at 80,000 miles should be uneventful. I switched ours over at 130,000 miles and at 165,000 miles the engine is still bone dry.

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Fred Hoelzle