That V6 needs synthetic to operate under (at the time, MB-specified) FSS a.k.a. extended oil change intervals.

AFAIK, dino oil is fine in that motor if you change every 5K or thereabouts.

And that's the way it is.
If you change oil as per FSS.
That does not mean a V-6 will not run " properly " on dino oil.

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2007 C 230 Sport.

well, fwiw, i figure i'll go ahead and change the oil every now & then