2007 Low oil pressure
I have a 2007 Silverado Max with 6.0L. The other night while driving home the check engine light came on and I noticed the oil pressure was at 20 psi, which is unususally low for the truck. The next day I drove down the road for about 2 miles and the oil pressure went to 0 and the warning message to shut engine off came on. Pulled over and checked oil and it was full. Cranked truck and message went off and had 15 psi of oil pressure. Drove truck home and oil pressure went to 0 again as I pulled in driveway. Truck has 62000 miles and oil has been changed regularly. Called the dealer and he said it would only be covered under warranty if its internal engine problem. So I went ahead and put a new oil sending unit on and its still doing the same thing. Crank truck and it has 15 - 20 psi oil pressure until you run it for a little while and it goes to 0. Dealer says to figure out what it is and bring it to them if its internal. The engine is not clicking or making any kind of bad racket. I also changed the oil just to make sure the filter did not have a clog or something. Anyone have any ideas? Should I just tow it to the dealer and absorb the cost if its not under warranty?