oil pressure drop once warmed up

[TurboWS6]

I had a very similar issue last year with my LQ9 pulled the motor and found this. My oil pressure was like 35ish cruising the highway hot. 45-50 cold at idle then 60 plus until it warmed up

Main bearing
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Notice how pretty much all the babbit material was gone, motor still had 35ish as stated above.

The culprit was the fact that the builder never put the bolt in the pickup tube to oil pump flange and the pickup tube slid out a little. All was good for about 25K miles then out of nowhere the oil pressure started dropping. Took this pick as soon as I pulled the pan. When I put it together this last time I used lock tight on that bolt just to be sure.
[IMG][/IMG]

Sorry man but your motor sounds like it doing exactly what mine was before I had the crank turned and put new bearings in. Its a PITA but you can pull it apart and fix it for probably 300 or so.