Zinc is not entirely kosher in diesels, now that they all have cat. converters and many diesel oils have less zinc than previously. I can only seem to find 2008-era info on the web about ZDDP, and am having trouble find detailed info for what is sold in 2013, in either gas or diesel-rated oils.
Oil manufacturers do a lousy job of stating what is in their motor oil at any given time. You would think this would posted clearly on their websites, but finding current, relevant info seems nearly impossible.
Colo Springs, CO