I've been reading about engine oil on the web, just for interest.
ZDDP, which is the most used anti wear additive is given a nice short rundown here:
https://www.experimentalaircraft.inf...rication-6.php
Castrol Edge is promoting titanium in their oil.
Both Penrite and Nulon oils use ZDDP, in the Mondeo recommended oils, according to their MSDS.
Penrite have this idea of 'full zinc' I suppose it's some sort of marketing mystique.
It would be nice if the oil blenders listed the ingredients like they do on vegemite jars.
MSDS are incomplete, they can avoid listing ingredients by claiming the are non hazardous.
ZDDP is known to be hazardous to aquatic life, so is required to be listed I suppose.
I don't lose much sleep on the oil issue, it's just interesting I reckon.