I have a 95 e300 with essentially the same engine, om606. Mine has just shy of 300k miles and exhibits the same symptoms, and I found the issue. Mine leaks from a o ring imbedded in the head gasket at the rear passenger side. If you look at a new head gasket you will see it. So mine leaks until it is fully hot, which I suspect the head expands just enough to seal, then as it cools in the garage I will get a couple of drips.

No oil in coolant or vice versa. I am making plans on pulling head and sending it to Metric motors for overhaul. I think I can get another 300k out of bottom end it runs so dang good. Not sure if it's the same on yours but check that rear passenger side closely, mine drips on bell housing.

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1995 E300 (W124)
1999 ML430 (w163)
2011 GL350 (x164)
2016 Sprinter 144" 4X4 lowtop (906)
2004 E500 (W211) 4matic Wagon (Gold)
2004 E500 (W211) 4matic Wagon Avantgarde (silver)