-Oil Additives and wear in new and older oils, 2 articles located here by professionals-
http://www.aera.org/ep/index.htmlIn these articles, you will see the additives that count, which are lacking today, and how to remedy. It makes sense.
-I found when changing filter and oil, the gasket on new filter is much harder to remove if I lubricate it during the new filter install with synthetic vs regular oil. Yes it is strange, but that was why I said it.
And lastly, the threads in a new filter often have small metal particles that you can wipe out with your finger simply, that are signifacant enough to make a grey smudge around the paper or rag.
I am for German Castrol 0-30 as the oil of choice.
Make sense?