Another oil thread, yay! The tests results are probably generally true, even though a lot of the comparison oils aren't used that much, and their lab isn't A2LA or ISO17025 certified. Sure, Amsoil makes great oil, but for me it's not worth the money- totally overkill. Oils these days are very good across the board. The most important factor when selecting an oil is the weight. All conventional oils with a viscosity range of 30 (such as 10w-40) will suffer viscosity breakdown. Engine designers knew this when specifying 10w-40. Thicker oils don't flow as well when hot, so they cool less effectively. Thicker oils can also cause the bypass valve in the filter to stay popped open. I have a suspicion that a modern 5w-30 is probably best in our engines. Why don't one of you guys try it and report back, I am stuck in my old habits of using 5w-40 synthetic!