I have a 2008 6.4. When I do a cold start or start after its sat for a little bit it throws the low oil pressure light. When it does this the truck kinda shakes like a rough idle so too speak. I'm in Ohio and running 15w-40 motorcraft oil and filter. Also the oil cap is ford OEM as well. Any ideas and help would be greatly appreciated.

 

Recheck the oil filter and make sure it is seated properly. I take it you replaced the oil filter yourself the last time? Verified it is OEM?