2004 GMC Sierra 2500 hd 6.0
 

I’ve been working on my mother-in-law’s truck for the past week with low oil pressure light coming on. I’ve replaced the oil pump, pick up tube and oil pressure sensor and still have maybe 10 pounds of oil pressure showing. It seems like oil isn’t getting to the top of the engine because the lifters are ticking pretty good. I’m going to put a mechanical gauge on it in the morning but any other advise would be greatly appreciated.