If you really want to know about oil, check out Motor Oil Geek (Lake Speed) youtube channel, Tribologist, Tribology is the science and engineering of understanding friction, lubrication and wear phenomena for interacting surfaces in relative motion. It is highly interdisciplinary, drawing on many academic fields, including physics, chemistry, materials science, mathematics, biology and engineering.
This is why I use Pennzoil Ultra Platinum Full Synthetic, was using Redline, but switched over after his recommendation.
Usually you can get 3/5 gallon jugs on Amazon for $68