00 F150 4.6 Engine Knock

Ok to start with the truck has 134,000 miles on it. Going down the road and the oil pressure goes to zero then back up then to zero then back up and so on. long story short engine ends up with a slight knock which gets worse. Installed oil pressure gage and verified that the pressure was fluctuating. Pulled pan with intentions of replacing pump and found that the screen was clogged. Cleaned screen and re-installed pan and verified that the pump is holding good consistant pressure now. Pulled pan and replaced all the rod bearings found some slight wear but nothing major. Now truck runs great holds consistant pressure but knock is still there. Sounds like it is coming from the rear passenger side valve cover. Checked for codes and it does not show any. Could this be from the knock sensor ? Or is that even possible ? Any and all help and suggestions will be greatly appreciated !
Thanks,

Probally needs another engine and it is horrible to remove the engine,blame the engineers for that.The book says to raise the body 4 or 5 inches.The 4.6 has detination problems,I have seen that.The piston ring lands break.The Jasper rep that comes in my father's shop knows all about it.Jasper puts the better and improved pistons in the 4.6L engine and recomends getting the computer reflashed after the engine replacement.