Well, this'll prolly stir up a hornets nest again - but - I went to Wallyworld today to get some oil for the ol' girl. All they carry now (at our store) is Rotella CJ-4, which is the "new" formulation. It actually has less ZDDP in it than the Castrol GTX 20-50w I've been using. According to the research I've done, you'll need to find the "old" CI-4 formulation to get more zinc than the Castrol GTX 20-50w.
