Depends on how much and how hard you'll be using her.If your intention is to occasionally idle around empty, to the tune of, say, 2,000 miles a year in flat country, the regular will be fine forever. If, however, you'll be pulling steep grades with a full load of topsoil, the engine's internal temps will be substantially higher. That being the case, I'd run, like, 90 octane and a lead substitute to help keep the valves lubed and cooler at the seats.
