low oil pressure

[woodbutcher]

I bought my 2013 GMC Sierra 1/2 Ton, 2WD with 5.3 engine new in 2013, and the oil pressure gauge showed low readings from day one. When it was cold it would show less than 40 psi, and after warm-up it was down around 30. I have 35K miles on it now, and oil pressure readings are probably 30 psi at best. The factory gauge doesn't show numbers, so I'm guessing. I'm hoping the O-ring on the pickup tube is the problem. Replacing it would be easier than replacing the pump, but I'll probably hire it done. Does anybody have experience in comparing the cost of this job to doing the oil pump replacement at the same time?

Butch
 

[Steve@Advance]

Those don't run very high oil pressure.

That's about what mine runs, same same truck, same engine.

I've never looked up the specs, but everyone told me not to worry, that's normal.
 

[JF in MI]

I ordered my Ford Club Wagon new in 1990. Always changed oil every 3k miles. After about 150k miles I noticed the pressure getting slightly lower as the years passed. I knew (from decades in the business) that Ford bearings were "softer" (some may argue this) and resigned myself that even though I kept up on oil changes the engine just plain wore down. Before pulling the bottom end off the engine I decided WTF, I'll try a new oil pressure sender first. Pressure went back to like when it was new. May be worth a try.
 

[gab]

My 2013 is about the same, I'm thinking it's normal.
 

[jniolon]

old adage I've always heard is you only need 10psi for every 1000 rpms the engines turn.

I had to put a new 5.7 in my 2008 suburban and brand new it only ran 30 psi at idle and about 40-45 at high speed... mechanics tell me that's plenty.. BTW I use Mobil 1 and change at 5k

john
 

[David G]

They have lowered oil pressure to reduce the parasitic load.

I would assume it is fine.
 

[Pete in Holland MI]

Same truck, year and engine here. 38 psi at highway speed, warmed up in the summer when new. 122,000 miles on it now, has dropped to 36 psi. Also use Mobil 1.

I wouldn't worry about it.
 

[Mark-Ia]

remove the oil sender unit and see if the screen is plugged.
Chevy Engine Oil Pressure Sensor


The Chevy engine oil pressure sensor problem has been going on for a long time. With that said, the vehicles with the most pressure switch problems fall in the range of V-8 engines from 2003 through 2012. At some point in the model year of 2007, Chevrolet realized an issue existed.

They decided to place a filter screen around the Chevrolet engine oil pressure sensor. They did this because they believed sludge and debris found its way into the sensor. Not only did this not fix the problem, it created another. Now sometimes when you pull the protective filter screen out, you find it completely clogged.
 

[DERM]

Did you check the pressure with a mechanical gauge? In nearly 50 years as an auto tech I replaced a lot of sending units. By the way an mechanic gets paid for his labor but a tech gets paid for his knowledge! LOL We all start as mechanics !
 

[Billy Shafer]

Most of the Onan engines. Start at 40-45 pounds. When hot drop to 30-38 pounds. I would guess that would be a normal range on that engine.
 

[buickanddeere]

Crank driven oil pump on my 6.0 failed on startup .replaced the plump with a high volume unit from Chev racing division .
Holds 30psi at idle 284$ over 200,000 on the engine .
 

[woodbutcher]

I've read about those. Sounds like the way to go.
 

[woodbutcher]

No, not yet.
 

[woodbutcher]

I'm using full synthetic Castrol. The oil pressure never concerned me too much, but it is lower now than it used to be.
 

[woodbutcher]

I've never seen this gauge show more than 40 psi.