I acquired this X3 about 2 month ago with 46K miles, right now i have 47***.
My oil service thing says 1500 till oil change today, i changed it last Friday and got my Blackstone report today.
When oil was drained it was filthy, and i mean if it had a dipstick i could pull out it would be scary to see something like that.
Based on this i'll be changing my oil at least every 7-8K, still using Castrol 0w-30 european formula or try Amsoil.
I dont see a way any engine will be able to work at its full potential past ~80K miles with such dirty oil, compression loss and oil burning are the first symptoms, way too much metals floating around.
I guess BMW doesnt care about long term reliability or long term customers.

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