Lower oil pressure after replacing oil sending unit

You could change the sending unit and see if it makes a difference. Cleaning the screen is a good idea. You can also use a mechanical gauge to check the electric system.

Just install a Delco PF6 for oil filter. This fixed the low oil pressure gauge reading on my 2010 Silverado LT with about 185,000 miles on it

Install a Delco PF6 for oil filter.

DELCO PF64

There is a little screen under the oil sending unit that you can clean or replace,,, what happens is older engines with lots of miles,,the reason is the oil shellac covers inside of engine,,, then or starts to flake of with time,,, or if you change to a synthetic oil,, it will make it flake off in very tiny flakes,, these are what stops the screen up under the oil sending unit, the screen is nessecary because it keeps the pump up lifters from getting clogged, and then they start ticking and will eventually need replaced,, this is part of active fuel management, where it drops to 4 cylinders while driving,,, take a small pick after you remove the oil sending unit, and insert down in the unit hole, hook and pull out, clean or replace,,,reinstall If your engine has many many miles you will have to do this several times a year,,,or pull the pan , oil pickup pipe , clean up in the engine for a real good cleaning, clean everthing real good and maybe if your lucky you won’t have any problems with stopped up screen for along while Screen part number GM (12585328) do your own research to make sure