I gave the Delo 5w40 LE and the 15w40 LE a try in my Detroit Series 60, for some reason, they both sheared pretty bad. They would drop to a 30w in an OCI. I have since moved over to Schaeffer oil and the shearing problem has gone away and I have almost doubled the OC interval. I always had high regards for Delo, but for some reason, this engine sure didn't. All other wear metals are lower with the Schaeffer also. Just one of those quirks in life. Delo has a strong reputation, that is why I ran it in the Detroit. It was really perplexing that it wasn't holding up well.