Originally Posted By: m6pwr
The cylinders in your your new M3, by the way, are DLC treated (diamond like coating). Very hard and durable. Maybe they, or the rings, don't require any kind of break-in. On the other hand, maybe they do. With all due respect, why do people think they know more than the factory engine development engineers when it comes to the care and maintenance of their cars?
Cylinder walls probably aren't DLC coated, just the rings, if that. Do you have any reference? I can't confirm your facts there with a google. The N52 BMW engine used to use Alusil aluminum cylinders only (no Fe liner), yet I think BMW went to Fe liners on all the newer stuff.
Originally Posted By: Bluestream
.then the ZDP rich assembly lube is washed into the oil and contributes to spiking the factory oil fill with extra ZDP....so....in fact, the factory oil fill does, by default, have slightly higher levels of ZDP to guard against breakin wear. Removing this oil and changing early does put less ZDP in the oil for the breakin miles that follow..
That doesn't apply here. Looking at the UOA, there isn't extra ZDDP in there, just a typical Euro-oil amount. I'm currently using a high-moly oil for break-in, as Honda formerly did that, and there was a tribology research paper that showed machine marks lasting longer with tons of moly in there.
Bottom line, its always good to get the iron particles out. Change is good here. Oil filter only catches down to around 10 or 20 micron particles, so a good oil drain plug magnet is great during break-in.