Low Oil Pressure Warning - 1st time ever

[Bleepster]

2011 Silverado LT 1500 5.3L - 115k

i know of the low oil pressure warning issues with these trucks.  I have owned mine since 60k miles and faithfully change my oil every 5k.  i have AFM delete done.  anyway - i had about 200 miles left before my next oil change, and we left for one last camping weekend.  it's only a 2-hour trip at 65mph.   I checked all fluids, all was great.  had to pull over every 30 minutes or so because I'd get the low warning and id have to shut off the truck.   i waited a few minutes and it fired right back up and oil pressure was at 40 PSI then steadily dropped over 30 minutes of driving until the lights came back on.  this scenario happened 3x on way up.  Saturday morning i went and had an oil change and now things are back to normal.  ran at 38-42 PSI pulling my trailer (26' alpha wolf) with no issues.

 

what exactly causes that?  did my oil mysteriously lose all viscosity?   should i have my sending unit and screen replaced?

i heard of the oil tube o-ring issues as well.  not sure how to verify if that's the issue or not.

 

ahyway - i think from now on i'll be changing at every 4k

[CamGTP]

I'd be changing out the sending unit and filter screen that is under the pressure sensor. A dirty screen or failing sensor can do what you are seeing.

[swathdiver]

Someone mentioned the same issue recently and I think the culprit was the oil filter.  My memory isn't so good.

 

Anyway, if you ever suspect the o-ring, keep an extra 2 quarts on hand, overfill the motor and drive on to keep the o-ring submerged.  We all thought this was to be temporary but a fella came on and said he was down on his luck and left it that way for two years until he could make the repair with no harm done.