Oil pump

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Denali GMC 87

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Got a question. My 2008 denali xl 6.2 with 222k oil pressure at idle read half way between zero and 40 at a stop and the goes past that once you start moving. Is that normal, I know it's been really hot and muggy weather also. Should I consider maybe throwing a new one in and also would it hurt to put in a high pressure, high volume +10 psi higher melling 10355HV.
 

j91z28d1

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you really should get a scanner and read the actual pressure and by it goes past that, do you mean when you Rev it up, the needle goes pasted the middle mark?


if so, it sounds like you're well within spec. but can't hurt to get a real number from a scanner instead of the guessing gauge
 
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Denali GMC 87

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Yes the needle goes up past the 40 psi. I have read that the pressure is low at idle. But when setting at a light tonight it seemed really low. However it is really hot and muggy and figure that may be why? Again, it did go back up to normal. I'll have to see if my scan tool will show that I think it might. I'll have to check. It's the Inova 5610.
 

R467X

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Are you experiencing any weird shaking or vibration? Has it done that for a while? My guess could be your oil pressure sensor starting to go. Use a scan tool to verify before you start throwing parts.
 

j91z28d1

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there tons and tons of threads about low oil pressure, quick search you can read till your eyes go crossed.


but just keep in mind gm service manual spec for minimum oil pressure is absurdly low. I'd have to double check but something like 6psi idel at working temperature.

if it's 20, it's probably just fine. Just alarming to see if lower then you're used to seeing.
 
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Denali GMC 87

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No shaking idles like a Swiss watch. I have read about it reading low of course researching. But I guess my next question would that be a bad thing if I did down the road installed the high volume high pressure pump?
 

strutaeng

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That pressure is just fine for a non-DOD/AFM engine. If it's not making any weird noises, keep on truckin'...

Replace your oil pan pickup tube because those do tend to flatten out with age and can cause issues as safety precaution.
 

R467X

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So I just did an AFM / VVT delete on mine and was going back and forth with Michigan Motorsports who absolutely advised getting a lower pressure pump than what I had there out of factory. My pressure, when warm after driving can go down to 18 and usually hovers at 18-22 when warm.

Basically, if you're not doing any performance upgrades, don't waste your time on any high volume pumps they are pointless.

It could be a number of issues but if you're not experiencing vibrations, shakes, misfires, no check engine lights then I wouldn't even stress this. Those sensors on the back valley cover are notorious for going out and are a pain to get to.

Do you know if your engine, when getting an AFM delete, if the little screen under the sensor was removed? Also do you know if your oil pan has the plug installed in place?

If you never had AFM, do you have VVT? I know the early 07+ variants had either or before they went to both like my 2011.

How often do you change your oil? Do you use quality synthetic? What viscosity are you running? Have you tried changing your oil and seeing if your pressure changes?
 
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Joseph Garcia

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Got a question. My 2008 denali xl 6.2 with 222k oil pressure at idle read half way between zero and 40 at a stop and the goes past that once you start moving. Is that normal, I know it's been really hot and muggy weather also. Should I consider maybe throwing a new one in and also would it hurt to put in a high pressure, high volume +10 psi higher melling 10355HV.
20psi at idle when fully warmed up is normal. You should read around 40psi at 2000rpms and above for normal.
 

j91z28d1

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So I just did an AFM / VVT delete on mine and was going back and forth with Michigan Motorsports who absolutely advised getting a lower pressure pump than what I had there out of factory. My pressure, when warm after driving can go down to 18 and usually hovers at 18-22 when warm.

Basically, if you're not doing any performance upgrades, don't waste your time on any high volume pumps they are pointless.

It could be a number of issues but if you're not experiencing vibrations, shakes, misfires, no check engine lights then I wouldn't even stress this. Those sensors on the back valley cover are notorious for going out and are a pain to get to.

Do you know if your engine, when getting an AFM delete, if the little screen under the sensor was removed? Also do you know if your oil pan has the plug installed in place?

If you never had AFM, do you have VVT? I know the early 07+ variants had either or before they went to both like my 2011.

How often do you change your oil? Do you use quality synthetic? What viscosity are you running? Have you tried changing your oil and seeing if your pressure changes?


that's interesting they told you to change to a lower volume pump after the afm delete? the interview I was listening to, millings suggested keeping the oem level pump on it even after deleting.

probably doesn't matter. Just thought that was interesting.
 

R467X

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that's interesting they told you to change to a lower volume pump after the afm delete? the interview I was listening to, millings suggested keeping the oem level pump on it even after deleting.

probably doesn't matter. Just thought that was interesting.
Yeah, I wasn't going to argue, figured those guys are subject matter experts.I haven't had a single issue.

I also deleted VVT so maybe that's why.
 

j91z28d1

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Yeah, I wasn't going to argue, figured those guys are subject matter experts.I haven't had a single issue.

I also deleted VVT so maybe that's why.


that could definitely help. the same interview mentioned the vvt can use more oil than the afm lifters. they don't seem to need a lot of volume to release. guess the vvt is always moving around.
 

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