Bought 2004 1500 5.7 with 202k. Was told by the owner that the oil pressure switch needs replacing. I replaced the switch and pressure went to normal. Changing the oil this morning and when I removed the plug...... nothing. Stuck a hex wrench in the hole and thick sludge came out. Let it drain for 20 min. Took some "decent" used oil that I hadn't recycled yet and half a gallon of Miracle Oil and let her run for about 10 minutes. Looked at oil pressure.... ZERO! Drained again put the other half gallon of Miracle Oil, let it run for about a minute, pressure good and shut her off. My question is how would you recommend I continue without dropping the pan?