My JD tractor gets the low oil pressure light (at idle, when hot here in S. FL) on dino 10-30, but not on M1 10-30. For whatever reason, the M1 seems to have a bit more hot, idle oil pressure.
Not sure this translates into anything meaningful. Even though the tractor works hard, the engine does not. Heck, sometimes I don't even run it at full power.
By the way, when running at less than full RPM, it actually runs a bit cooler according to my IR thermometer.
Chris