Why such thick oil??
Amsoil has ZDDP, so does Valvoline, and I believe Pennzoil Platinum does too (only pennzoil I would ever run.) all > mobil 1
"THE LAST TWO NUMBERS HERE ARE THE PHOSPHORUS LEVEL THEN ZINC LEVEL
AMO 10W-40 Synthetic Premium Protection 1265 1378"
You are absolutely right and I thank you. That's what I'm getting.
You don't need that much ZDDP on a low compression engine that is fully broken in--more like 800.
You don't need that much ZDDP on a low compression engine that is fully broken in--more like 800.
What you can do as well, is have your oil tested at a lab. I used to work for Oil analysis lab, inc. located in Spokane, Washington. Having your oil tested can tell you SO much more than just looking at or smelling your oil. Their site is www.oillab.com It is a small independantly owned place, many large companies send their oil to them for testing.
from what I understand the requirement for higher ZDDP levels is the fact our engines are flat tappet, as opposed to a roller cam.
preventative medicine
I haven't had any problems with the 15w50, but I've been thinking of trying a lighter weight. By the way, the 50 doesn't mean the oil is viscosity 50, it means it acts like a 50 weight oil would at 250 (?) degrees F. (I'm not sure about the exact temp.) When 50 weight is heated to 250 degrees it gets quite a bit thinner.
So if I put in a new set of roller rockers, this concern is completely eliminated (essentially)?