Low oil pressure at idle?

Dana67Dart said
You could go to 30 weight and see if you gain anything.

My old tired 150,000 273 flickers the oilpresure light on 30 weight, on 40 weight, no issue.

Wonder if the cam bearings are falling out of it. Seen so many just lose the lead and piss...wait it's not a dinosaur motor.
Check the pump.