I believe that the following may be an example of an additive that you cannot see.
A lubricating composition for use in the crankcase of an engine comprising (i) a base oil; (ii) one or more organo-molybdenum compounds at a level sufficient to provide from 50 to 500 ppmw of molybdenum; and...
From what I have seen in the FA20DIT (old uoa's on nasioc), there was not much difference in the rate that break-in wear washed out in 3k mile or 5/6k mile OCI's.
The Si in my XT was 28 at 24,257 miles and 21 at 28,743 miles using paper filters and ~4,500 OCI's. Cu was 14 and 7. Si seems to...
Why do you or this geek presume that all Euro spec oil has high calcium? Are Subaru DI engines prone to pre-ignition? Why does Subaru Japan allow Euro spec 0W-30 across most of their current line-up? Even in the FB20 Crosstrek.
What oil was used previously? It's possible that higher zinc can affect the copper leeching from the oil cooler.
Here's my uoa just a few hundred miles before my banjo bolt screens clogged and caused turbo failure. Copper was in the single digits although lead was elevated...
From the Subaru uoa's that I've seen there doesn't seem to be much of a difference with fuel for people that mention highway mileage. I do believe that fuel dilution is higher in the winter which is why I've decided to stick with 5W-30 year round.
Do you know what your oil temps were? Sometimes...
What is this based on? I would like to read more info about how these brands are rated in regards to their formulations. I do not want to recommend Castrol to anyone if it is surprisingly poor.
Thanks!
Do you still have the AVCS and turbo banjo bolt screens? 5k mile OCI’s shouldn’t be a problem if you do. You can probably push the intervals longer if you don’t have the screens.
Amazing that you’re not burning oil. I moved to 10W-40 when I had my FXT because of consumption.