Sal Briseño

I am currently having issues with my 2006 Chevy Silverado 5.3L V8. It has approximately 220k miles. When I start the truck the oil pressure is fine. After driving for a while the oil pressure drops down all the way to the red while idling. There isn't any noises coming from the engine. Once I begin driving, the oil pressure jumps back up to the 35 range. I come to a stop and it drops back down in the red.
I did put the Lucas oil stabilizer in it and it ran good for about a month. Then it happened again. I do have an oil pan gasket leak. Not sure if that adds to the problem. I changed the oil sensor gauge and still having the same problem. Anyone run into similar issues? What could the problem be?
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2001 chevy silverado

#1 make sure you are UNDER THE MAX LINE WHEN YOUR ENGINE IS HOT, under it visibly. this means when cold you should be say 1/2 into the hash marks OR LESS. that's a max fill line not "normal" line.

#2 it's supposed to do that. your oil filter has a ball that holds pressure (say, less than 60 on rev) until the engine runs a while and it drops (say, 40, a little higher during revs)

#3 the dipsick is the original OEM dipstick for your VIN right? if you think the dipstick was replaced (looks too new / different from photos on other same model cars): check it against a know good one (you may have a bogus fill line)

USE THE CORRECT OEM OIL FILTER

#3 you have not listed any oil pressure data

tech2

to the op
when the oil is cold the viscosity is higher so the oil pressure will be higher also.

an oil pump is a positive displacement pump....the faster the pump is turned the higher the volume of oil pumped....this pressure is controlled by an oil pressure relief valve in the oil pump.
to high a pressure will wash out the bearings so max pressure must be limited.

to create pressure, you need restriction. if the bearing clearances are to large due to wear; the oil pressure will be lower.

you will most likely see lower oil pressure at idle, oil warm. The question is.....is this due to a worn oil pump or worn bearings? Yes, verify proper oil level and viscosity.
you can put a master gauge and verify oil pressure....min spec is 10psi per 1000 rpm until the pressure relief valve opens. If the pressure is confirmed low I have listed 2 reasons. You can either fix the problem or run a thicker oil.

southland361

I would look into maybe a weak oil pump or the o-ring pick up tube. I have an 04 and jus went ahead and installed a new pump and o-ring jus for the hell of it. I wasn’t losing pressure, my gauge would fluctuate a lil.