Was at Rural King yesterday and grabbed a 5 gal bucket of Rotella 15w-40, was thrown off a little because it was a yellow bucket instead of white and a different label than what T4 normally is. As i was checking out i realized it was T5 and not T4, but rang up as T4 at $59. We run 15w40 in our older farm equipment and dump trucks, so i'm now wondering if i should go back and get some more at the same price. Or if there isn't much of a difference i'll just stick with grabbing a bucket of T4 whenever i need it.