I've never seen Shell Rotella in bulk around here.
My oil comes in a 300 gallon jug. Lol. I think we're rocking Gulf 15w40 right now. 15w40resists shearing well, and little semi truck engines are easy on oil. Many drink it quicker than it wears out. So, that's kind of a weird oil change.
Not necessarily, semi trucks will add maybe a gallon every 15-30k. Again look it up. More than a few otr guys got several hundred thousand miles on the same oil.
