Low oil pressure warning.

Last week the 03 Silverado 1500 gave a low pressure warning. I stopped, made sure nothing was leaking and drove home slowly the 3 remaining miles. I changed the oil as it was almost due and it took a long time to register oil pressure.
My question is, sensor or real problem? Or just change the sensor and see it it keeps happening.
Also, the internet machine says something about a screen clogged on/near the sensor that i dont quite understand.

Did you check the oil for any of that glitter? Do you still have the oil filter to cut open?

What engine?

None of these engines had that filter, that was on the DOD/AFM thing on the GMT900 series.

Hook up a mechanical guage before replacing the sender.

I had the same thing happen to my 99 Silverado 4.3. Saw glitter after replacing the sender and hooking a mechanical guage and it revealed "real" low oil pressure (about 5 psi at hot idle.) I saw the marking on the wall when I saw the glitter...

5.3/
no i wasnt smart enough to look at the oil before i dumped it. i could probably identify the oil filter and cut it open though

I have an '03 as well. Just last year I suddenly had lower oil pressure. Turned out to be an 10 cent O ring on the oil pick up tube. After 23 years the O ring was flat on the outside and sucking some air. The AWD made it expensive to fix (had a good mechanic do this job ;D ). Apparently you have to drop the oil pan, which involves partially dropping the front differential to get at it.
I have also heard that oil sensors going bad are common as well

To check for oil pickup tube o-ring problem, park the truck pointing downhill at a decent angle. Usually backing the rear tires up on a pair of ramps is enough angle. Add 2 quarts to the full amount that is already in the oil pan. Start the engine and if the oil pressure is all of a sudden good, then the o-ring needs changed. If you delay that work and do not change the oil right then, drain the 2 quarts out before driving.

Does not have the screen, like @stutaeng said. If you change the sender, attach the oil pressure gauge before installing the new sender and do an oil pressure test.

Checking for glitter. Cut the filter open close to the roll seam where the threads are. You can pull the guts out. Then, like panning for gold, pour a little oil out on to a clean white rag or paper towel, a couple thicknesses thick. Look thru the oil. then tilt the cannister a little and look above the oil and see if you see glitter in what is trying to drain down to the oil puddle. Cut the end of the filter pleats and look inside the filter pleats. If you cut out a section of pleats, pull/stretch them open and look for the glitter. If you see ANY glitter, that is bad.

I like to use a magnetic drain plug, too.

Darn, i forgot about magnetic drain plugs. They used to be on all sorts of things

SK101 said:

Darn, i forgot about magnetic drain plugs. They used to be on all sorts of things

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You are not saying what you are driving but my 2005 Tahoe Z71 with a 5.3, uses a Dorman oil drain plug #090-091 with the magnet

I thought all of these vehicles had a factory magnetic drain bolt, no?

They may originally, BUT, who would still be using the original one? Should be changed/replaced every other oil change. The seal that is built in under the bolt head, does not last and seal much longer.

Well, now i am going to have to look when i change oil from now on.
Hopefully its magnetic and i dont know because its never had filings on it.

SK101 said:

Well, now i am going to have to look when i change oil from now on.
Hopefully its magnetic and i dont know because its never had filings on it.

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Let's put it this way, it is not supposed to have metal on it. If is not magnetic, you would not see the metal anyway.

The old, "Out of sight, out of mind"!

SK101 said:

5.3/
no i wasnt smart enough to look at the oil before i dumped it. i could probably identify the oil filter and cut it open though

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You’d seee it in the pan because it would reflect more Light than normal

Mine is original and it’s just fine. Clean the o ring seal and it can be used for years. But don’t over torque them. Pretty sure it’s replaceable

ORVietVet said:

They may originally, BUT, who would still be using the original one? Should be changed/replaced every other oil change. The seal that is built in under the bolt head, does not last and seal much longer.

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Yes the tip of the drain plug is magnetic and it should have a moderate level of debris on it