So it turns out the oil pressure gauge is a semi-fake. It will show the real oil pressure value if it is between 20-75psi, but if it's below 20psi (and above 1psi) the gauge just shows roughly 20psi.

Was looking at some other data on my scanner and noticed that my idle oil pressure is about 9.5psi. The service manual states that the minimum oil pressure for curb idle is 6psi, so technically I'm within spec but that sure seems low to me. My engine has 180k on it, so I imagine the bearings are just getting loose and it's about time for a rebuild...but just for ****s and giggles could a few of you guys with scan tools post up what your hot idle oil pressures are? I'm curious.

 

For what its worth, I boosted my oil pressure a bit on my 5.9 motor by swapping out the original oil pump for a new high volume oil pump. I also changed out the oil pump pickup, as the stock units are known to accumulate sludge in the bottom of the oil pan. I also run 10W40 conventional oil. Oil pressure increased and stays within the acceptable limits of the factory gauge.

 

I had my pump off a while back when I did the rear main seal. Cleaned the pickup out real well and re-installed it. It pushes really good oil pressure at any speed above idle, so I don't blame the pump at all. I'm sure it's just sloppy bearings.

 

Mine is 21psi at idle according to my Autel

 

Cold or at operating temp?

 

Operating temp. When is cold the gauge shows above 40 never had a scanner hooked up cold