My chevy Silverado has about 203,000 miles on it and I’m have an issue with my oil sending unit. I’ve replaced it twice with in the last two years. Does anyone have an idea what would be causing this issue to happen about every 10 months.

 

Welcome from WA to Chevy! Please describe in more detail what you are seeing to get a better answer!

 

Welcome from Florida. Why are you changing the oil sending unit? Is reading wrong or just not working at all? There is a little filter screen under the sending unit, are you cleaning that when changing the sending unit?

 

yes that was replaced both times. After about 10 months when u start the truck cold the gauge reads 40 psi then will drop under 20 psi as the truck warms up.

 

You can try a heavier oil to see if that solves your problem. You can also install a mechanical oil pressure gauge to see if the readings are accurate.

 

Sounds right on the money for a rig with that mileage. My 93 Sub with 350k on it drops to 5-10 psi when warmed up. I think you are changing a part that is working correctly!

 

My '03 4.3L was running around 20 psi hot when I bought it. Changed the oil pump when it got down to 10 hot. Runs 20-22 hot now. I'm wondering if changing the screen fixed your initial problem and then 10 months later you started loosing pressure for real, although I would have expected a clogged screen to effect your reading both hot and cold. Did your cold reading also increase when you changed the screen?

 

When the dealership changed the sending unit they also changed the screen. After they installed the new sending unit and screen it works fine maintains 37 psi