I have a 2017 Silverado 5.3L. Used to stay around 40 pounds of oil. Now when idling, is goes down to 20-25 ish pounds. It’s not throwing any codes up but does have a bit of a knock if I floor it without letting the pressure build back up first. Cold start it’s just below 40 pounds but at operating temps (210) it drops like crazy. It’s not oil quality or level, I just changed it last week and it was good for half a day and went back down.