Air cleaner is going to be an oil bath type unless someone changed it out.

I would assume (and what I do), use the same type of oil in the IP that is used in the crankcase. I figure if the later models get their oil supply from the engine, that would make sense.

Some have said to use a heavier oil. Not to start an oil thread here, but the last time I changed the oil in my IP, a leak started. I use Mobil 1 synthetic in all my engines and I have to say, while the oil performs better at cold temperatures and probably lasts longer, I also now have minor oil leaks in everything, including my SUV & my lawnmower & pressure washer. I am not sure whether to blame that on the oil but it seems a bit too coincidental.

Anyway, enjoy your 220D. It'll probably be fine to drive around as is, but make sure you can stop OK (!)

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1976 240D "Katja"