Rotella 15w40
It’s a consumable and most here are on short oil change intervals I’d theorize. The marketing involved to get you to buy in the first place of any particular premium brand over any another is nonsense IMO “when”: any long term benefits are never going to be realized when you drain your oil often, or when your adding quarts to an engine that uses or leaks it. Nobody in the hot rodding world is concerned with how many miles they get out of an oil. Me? When it starts getting darker and I’ve got a few thousand miles on it it’s out of there. I want oil that lubricates and a filter that filters up until I dump it out for more that lubricates and filters. Haven’t found an oil or filter that hasn’t done those things yet. Warren Oil up to high $$$ synthetic Silkolene and everything in between.