From what I've checked into, all of Valvoline's oils seem to have a higher ZDDP level than others. Royal Purple also has a high ZDDP content, and so far as I've been able to find, is the only full synthetic avalable in a straight 30 weight.
One thing I'd like to add, it's not the reduction of "zinc" that is the issue. It's actually the phosphorus that does the anti-wear, the zinc is mainly just the carrier for the phosphorus. It's also what mucks up the catalytic converters in modern cars.
