Read what Marc has to say about required levels of zinc
Next, use google to find the zinc levels in the various oils available to purchase.
Click
HERE for a Mobil Table. You might also find some useful info
HERE not a recommendation, just saying
Secondchance is correct ... too much zinc is bad for the cats. For those of us fortunate to run without cats then the zinc shouldn't be harming anything. But if our engines need a certain amount of zinc (
again, refer to Marc's findings) then locating/using the oil that meets those specs seems a prudent course of action and that's why I'm using Amsoil AMO 10-40.
I live in a part of Georgia that was originally plantation land and still has a number of large farms that use heavy diesel equipment ... one of those farmers is a friend and he ALWAYS has Amsoil 10-40 on his shelves (it's the primary oil used in much of his farm equipment ... tractors, combines, harvesters, etc.) so I'm fortunate that I always have quick access to my Amsoil needs.