my 5.0 loses oil pressure after it gets warmed up & sounds like a diesel engine? on 1997 Ford Explorer

after it gets warmed up or if i accelerate it or rev-it up...i lose the oil pressure, and it sounds like a 7.3 Power Stroke, boy don't i wish. i'm limited on funds, and i can't work on my truck where i live.

Asked by for the 1997 Ford Explorer
sounds like oil pump going out or screen plugged up. oil pan will have to come off to check. engine has to come out.