If you can, yes, that unpressured bearing sound is maybe why some manufacturers say go two oils changes for one filter, very bad. You don't need to measure anything to know knocking your main bearings without oil pressure is bad, the less the better. I don't know why the full flow filter is used, the filters aren't very good at filtering, and then it's right in the path to the main bearings with all the resulting issues. A bypass system seems much better.