Problems with oil pressure

[Bigtimer]

I cranked my trucked up on Wednesday and was heading to town. All of a sudden an alarm went of and the DIC read "low oil pressure, turn off engine" ! I looked at the oil pressure gauge and it was on 0. So I checked the oil and it was fine. I took it to a local mechanic whom I trust and he assure me that it was the oil pressure sensor switch so I had him change it.

On the way home the alarm sounded again and the oil pressure was at 0 on the gauge??????? I took it back to him immediately and he recommended that I take it to the dealer. The dealer recommended that I drain the oil, remove the filter, and install a quality oil filter, 5 quarts of 10w-30 oil and 1 quart of Lucas oil treatment. Oh, the dealer hooked up an oil pressure gauge and it showed 40lbs of oil pressure while my oil gauge in the dash showed a touch above 0.

Have any of you been through anything like this before? Any help would be greatly appreciated.

 

[oldman7789]

Yup, 2008 5.3 300,000,miles oil pump replaced @ 180,000 and again at 300,000 was doing the same thing pressure would go away suddenly with no rhyme or reason then return just as suddenly. new pump and sensor each time fixed it. don't know why it does that, could be because the pump is not gear mesh as the older ones were but roller bearings spinning around in an enclosure. the symptoms and solutions you described could be a carbon copy of mine. don't worry, that 5.3 is bullet proof.