Low oil pressure (15 psi) !!

Lucchini · June 23, 2019

Jacob,

what year is your truck and is it the 5.3? I believe this lower oil pressure is on the 2014 to 2018 trucks.

My 2001 never goes below 30 psi.

I agree 15 is nerving thou.

Lucchini · June 23, 2019

79Mercy,

Good to know that your truck does the same thing as mine. Another step closer to thinking it’s normal to go this low. Hope it’s a piece of mind for you as well.

swathdiver · June 23, 2019

5 hours ago, Paintor said:

In the old days, 12 volts was sent to alternator to kick on charging system when key turned on. Resulted in overcharging of batteries. PCM now cycles alternator on and off to keep from boiling the battery off.

0 weight oil in Cali in hot temps getting low oil pressure....no fear.

You can get a 5.3 with 20k miles from a crashed truck on Ebay for $2k. Keep trusting GM and just drive it. Insufficient Oil Pressure= AFM lifter failures via the Melling Bulletin from last year. They make the collapsible lifters for 4 cylinder shut down.

https://www.melling.com/wp-content/uploads/2018/03/Melling-tech-bulletin-on-GM-LS-Deactivation-Lifter-Issues-3.1.18-1.pdf

Read what Melling says oil pressure is supposed to be.

That bulletin is for Gen IV LS engines. The oiling system and pump is different in the Gen V LT engines.

DirtyAndy · June 23, 2019

DirtyAndy, it would be great if you got back to me on this. Problem is you have to drive it for over 30 to 40 minutes to get the readings that low, as far as how mine is.

Thank you guys for all these great replies. So you guys are actually getting as low as around 15 pounds PSI according to the lines on the gauge in the dash?
The more people that chime in on these low oil pressure’s of about 15 PSi, on this model year, I think, will make a lot of us feel better that it’s very likely normal . I would’ve been OK in the first place, if it was a little above 20 psi at the lowest reading . All my other previous trucks, never went below around 30 psi stopped, at idle, in gear, after a long drive.
The more people that chime in, give us a better idea of how these new trucks really are or what to expect...

This is mine after a slightly spirited 30 minute drive and after idling for about 15-20 seconds in gear.

Lucchini · June 23, 2019

Thank you for the update DirtyAndy. Yours looks to be about in the 21/22 psi range. That’s where I think mine should be, but mine may read around what you have if I drove for 30 minutes in somewhat colder weather. Here in California today we have low 90s weather and in 30 to 40 minutes of driving it does go to 15/16 PSI.

Do you guys think that I should bring the truck in for this low of pressure? I would be much more OK about it, if it was to rarely go below 20 psi

Jacoby · June 23, 2019

17 hours ago, Lucchini said:

Jacob,

what year is your truck and is it the 5.3? I believe this lower oil pressure is on the 2014 to 2018 trucks.

My 2001 never goes below 30 psi.

I agree 15 is nerving thou.

2017 5.3L

I don’t run 0w-20 oil either. No reason to run an oil that thin in the TX heat.

1SLOW1500 · June 23, 2019

I ran 7quarts of royal purple 0w20 and dropped under 15psi. Last quart was a additive I got from a guy involved with the performance engine development. Said run it for a week then check oil and adda oil to cover what is missing.
I thought about a thicker oil. But he and others said don't do it. There are good reasons they spec that oil and that pump. Absolutely it voids warranty if they catch it. And they do send samples out for testing. The clearance, temps, and weight is picked based on engineering specs. Will heavier oil hurt your motor short term? Maybe not but maybe. I just don't see a reason other then seeing the needle looks better on dash.
I added a gauge that data logs and has adjustable levels for temp and pressure. So I will know. And as insaid I would worry more if I had afm/DOD

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Lucchini · June 24, 2019

1Slow1500, What year truck and size engine do you have? If you had my truck (2018 Sierra SLT Z71 CC 5.3) brand new with only a couple hundred miles on it when you noticed it. and have oil pressure go to as low as 15 psi (according to the factory gauge in the dash) at stop lights after fully being heated up (30/40 minutes of driving) with OEM 0w20 oil, would you take it in to have it looked at?

Lucchini · June 24, 2019

Jacoby, Thank you for that updated info on your first answer. I’m sure if I put thicker oil it would bring the gauge to more of what I would like to see. I would say this because when the engine is cold and the idle just drops to 500/600 RPM, and the 0w20 oil is thicker. I get between 30 to 40 psi while idling in gear. Of course when it heats up to full temperature that changes ....

1SLOW1500 · June 24, 2019

1Slow1500, What year truck and size engine do you have? If you had my truck (2018 Sierra SLT Z71 CC 5.3) brand new with only a couple hundred miles on it when you noticed it. and have oil pressure go to as low as 15 psi (according to the factory gauge in the dash) at stop lights after fully being heated up (30/40 minutes of driving) with OEM 0w20 oil, would you take it in to have it looked at?

Great question and the answer is involved. But answer in short is no. I would research as you are,keep a eye on it. And stay on good oil changes with the bill of each oil change saved in a fill. After the break in and oil change done i would then and only if it still worried me have it dropped off for service.
And when I did that know what you.want the written complaint to state and get your full printed code report and the copy of the service invoice. So if if has.to go back your perfectly prepared and if GM reviews it all they see the the most perfect service complaint and document.
Like the old saying always be the smartest man in the room or keep your mouth shut long enough to learn, then state you point.
Number one reason a gm service complaint is denied is the written service request
Number two is the customer

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FlipZ71 · June 24, 2019

My 2015 5.3 at 80K miles

Lowest I see on mine is 30 Hot.

I do run a 5w30 but when I switched there wasnt much of a difference in pressure , 2psi.

Have a buddy with 2018 , 6.2 8spd

His drops between 15 and 20 when hot .

Lucchini · June 24, 2019

1Slow1500, Thank you for your suggestion.

Sounds like you feel it’s normal, but to have it at least documented would be a good idea. That’s why I started this thread is to see if other people are getting the same pressure using the suggested 0w20 oil. If enough people chimed in saying they get similar results (well under 20psi) under the same circumstances, I would not even take it in. So when other people see this thread they will easily be able to tell if they’re concern with oil pressure in these new trucks is legit or not.

So far I think I may just take it in to get documented like you had suggested.

Lucchini · June 24, 2019

FlipZ71, Maybe they changed something with the 2018 models for the oil pressure? Did your buddy do anything about it with the dealer on oil pressure that low on his 2018?

FlipZ71 · June 24, 2019

No , he didnt take it in. Just keeping an eye on it

Jacoby · June 24, 2019

10 hours ago, Lucchini said:

Jacoby, Thank you for that updated info on your first answer. I’m sure if I put thicker oil it would bring the gauge to more of what I would like to see. I would say this because when the engine is cold and the idle just drops to 500/600 RPM, and the 0w20 oil is thicker. I get between 30 to 40 psi while idling in gear. Of course when it heats up to full temperature that changes ....

They only spec 0w-20 on these trucks to obtain their unachievable fuel mileage numbers. Plenty of other models that share this motor (block) that spec 5w-30. So there is no issue running a heavier oil despite what one other person said. There is a multi page thread on here somewhere about using a heavier oil for obvious reasons and the consensus is that it won’t cause any issues. With that said I probably wouldn’t run a 40-50 weight though. No issues running 30

10 hours ago, FlipZ71 said:

My 2015 5.3 at 80K miles

Lowest I see on mine is 30 Hot.

I do run a 5w30 but when I switched there wasnt much of a difference in pressure , 2psi.

Have a buddy with 2018 , 6.2 8spd

His drops between 15 and 20 when hot .

Same with me when I made the switch. With 0w-20 I wasn’t getting low pressure, was still seeing around 30psi hot idle. I simply made the switch because I think 0w-20 is too thin of an oil for hot TX climate.

Edited June 24, 2019 by Jacoby