Rotella has also been re formulated with lower zinc content. It used to carry a diesel CI-4 rating. Now has a CJ-4 rating. Try Valvoline VR1 racing oil. 10w-30, 20w-50 and a straight 30w are available. Very good zinc content. Look for the bottles that say "not for street use". Thats the good stuff...LOL.

G.