Hi. I am new to the forum and need some help. Was driving along today and noticed a clicking in the engine. Sounds like valves knocking. My thought was that I needed to add some oil. Before I could get to Autozone, my Oil light came on and the gauge dropped to zero. Pulled over, killed the engine, checked under Truck for leaks, (none), checked the oil level, was full. Started the engine and the gauge went up to normal, but still hear the valves knocking. Drove a little ways and lost pressure again. Killed the engine, started back up and the gauge went back to normal. This scenario repeats itself over and over. Just changed the oil 2 weeks ago, and the old oil drained normal, no gunk. Have been told by one person could be oil pump screen or oil pump going bad. Another person said if the oil came out clean, should be nothing wrong with the screen. Please, some of you knowledgable guys give me some ideas!! My Truck is a 2000 F150, 4.2L. I use Ford Motor Oil and Filter.

 

Mine did the same thing. I never did find out why. I was using Mobil one 15-50. I drained it out and added Rotella 15-40 and the problem never came back.

2001 4.2 V-6

 

That stuff is too heavy for that engine. The factory recommendation is 5w20. Today's engine clearances are too tight for heavy oil.