No oil pressure on 5.4 Triton
I have a 2005 F-150 with a 5.4 Triton. It does have quite a few miles on it, 200,000, but it has always ran fine and I drive it every day. A few days ago I drove about 2 miles and I could hear a noise in the engine, then it lost all oil pressure. I immediately shut off the motor and coasted to a stop in neutral. After it had slowed down a little bit, I could easily hear something spinning in the motor and it was even a little "grindy". Then, just before I came to a complete stop, I could hear/feel something catch and the noise stopped on one side, but there was still another side making the same noise. A couple seconds later it caught and stopped. This was before I had made a complete stop. Then, I can restart the truck and it has regular oil pressure until I drive another mile or so. Any ideas? The local mechanic looked at it and said the oil pump was good and he couldn't find anything wrong with it.