Oil type

[70bigblockdodge]

If it has a API circle on the back it has limited zinc to work with cat life.

 

[67newport]

Results in on Three More Diesel Engine Oils

 

[twostick]

That Ford Super Duty 10/30 should be good for guys that would prefer a lighter weight oil.

Kevin

 

[66Newyorker]

I use Lucas Hot Rod and Classic motor oil 10w40 has like 2100 ppm zinc, if I remember correctly.