Here is my reasoning behind using M1 0W40: I have seen thousands of UOAs and testimonials here on Bitog since I joined that formed my thinking of "If an oil is good enough to meet Porsche A40, MB229.3/229.5, VW 502/505, then it should be more than enough to protect ANY of my daily driven cars". The fact that apparently many race teams use M1 0w40, regardless of what oil companies sponsor them, gives me piece of mind with that oil choice. I don't have the ability and resources to rebuild and remeasure my engine internals every few weeks, so I'll rely on the oil choice of those who do just that between races. Cheap insurance, so to say. Yes, daily driver is not a racecar, but still.
Here is the reason for this thread: I gave my friend plenty of reasons and examples behind why I am using M1 0W40 in all my vehicles, but he had a hard time explaining his reasoning behind why all cars should switch to 0w20. His main points were:
- It flows better when cold.
- Nearly all manufacturers switched to 0w20, so all cars made in the last 25 years have no reason not to use 0w20 as well.
Neither of his points were convincing enough, so I turned to the biggest oil forum to see if anyone shares and exercises the views of my friend, and could provide more convincing reasons, or factual proof, of why 0W20 grade is superior and should be used across the board.