I know that this has been discussed many times, with conflicting opinions, and I am still confused.
What is a concern for me is the removal of zinc from modern day oils.
I have used Chevron Dello 400 30W for many years in all my diesel tractors and small gas engines, Including my backhoe.
I have a 1976 MGB with 9K actual miles and have been using Chevron Dello 400--15W30.
Now I am told, and can't find conflicting information, that zinc has been removed from all of today's oil.
I am looking into adding a ZDDP additive if necessary but that can cost nearly as much as the oil
Blame another one on EPA