I reached out to Castrol to see how much zink is in the different oils they have
here’s the response

Thank you for contacting Castrol North America.
​
Castrol does not publish any formulations or changes in formulations. Our additive systems and base oils are proprietary and chosen for performance and suitability first. Castrol uses only the highest quality materials, including synthetic base oils.


Thank you again for contacting Castrol. We value your patronage!


Castrol Consumer Relations

 

you will find nearly no zinc in any modern oils. Even ones that advertise with "higher levels" are miniscule compared to what you used to to get. Modern engines don't rely on zinc anymore as an additive, and it ruins catalytic converters.

If you're concerned about zinc content, get an actual additive and pour it in

 

I was just curious as there was a topic here last week regarding best oil for our engines
and it was brought up that a lot of you use diesel oil because of the added additives

i just found it funny how Castrol does not want you to know the details

 

Go over to the bobistheoilguy.com forum and look for VOA (virgin oil analysis) reports for the oils you are interested in.

Yes, zinc is still used... but not in all oils.

 

That is strange. I thought most companies had to have some sort of MSDS for their hazardous material.