Low/No Oil Pressure After new Oil Pump Install

[nadthomas]

I'm not real familiar with the LS series engines, but does the pick-up tube rest near the bottom of the pan, and is there a chance that it's too close to the bottom causing the oil to be restricted when being sucked in?

I know on some engines the pick-up tube needs to be adjusted to be about 3/8"-1/2" above the bottom of the pan.

2001 Yukon SLT
2012 Yukon XL Denali
2011 Yukon Denali RIP 5/20/18

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I have heard of that as well, but I don't think that is a thing with these and most modern motors. Someone correct me if i'm wrong. Although, i may try to pull the oil pan, so I'll inspect it if I do. I have heard that its possible to drop the AWD system a couple of inches to pull the pan.

 

[clandr1]

While I had the engine out and partially apart, I decided to replace the oil pump and the pickup tube.

I'm no expert on these motors, but am a huge fan of Occam's Razor (the simplest explanation is often the correct one). I'm wondering if your replacement oil pickup tube was out of spec when you installed it. I suppose if it's too high in the pan, or too low, that might cause some issues. Also, you might want to do a flow test to make sure there isn't something inside the tube that is impeding flow.

Do you still have the original pickup tube? If so, might be worth swapping it in and giving it a go to see if you get similar results.

Sorry I can't be more help - you've already done way more to your motor than I have with mine.

 

[01FormulaTA]

What about the O Rings on your valley cover? Why did you even replace the pick up tube? Why not just replace the o ring on the original tube?

Also I know the 07 L92 doesn’t have AFM however the early L92s DID have AFM components...LS engines with AFM used a higher volume pump than non AFM LS engines...the AFM pumps use a thicker gerotor with a larger OD than the 12586665 standard volume pump. The AFM pump is identical to the 12571885 high volume oil pump but uses a different spring...try part 12612289

 

[nadthomas]

What about the O Rings on your valley cover? Why did you even replace the pick up tube? Why not just replace the o ring on the original tube?

Also I know the 07 L92 doesn’t have AFM however the early L92s DID have AFM components...LS engines with AFM used a higher volume pump than non AFM LS engines...the AFM pumps use a thicker gerotor with a larger OD than the 12586665 standard volume pump. The AFM pump is identical to the 12571885 high volume oil pump but is uses a different by-pass spring...try part 12612289

I replaced the pick up tube because it was cheap and easy to replace with the engine out. I also did it to help ensure I had a 100% clean pick up screen, and to make sure I had the right o-ring.

Hmmmm I don't recall o-rings on the valley cover, and I didn't snap any pics of it when I had it off. Although I know my valley cover is different( ie flat) since I dont have afm. I think you may be confused, I know they later added afm to the L92 without other modifications, but I dont think my engine has any of the afm components in it. If there are o-rings on the valley cover that I missed, i could see that being a problem since the main gasket is new, the old o-rings would probably not make a good seal now. Sounds like a good thing to check since I would need to pull the intake and valley cover to install my lift plate if I end up pulling the motor again anyways.

 

[kbuskill]

How about oil filter?

Also what about the oil pressure bypass in the oil pan?

 

[nadthomas]

How about oil filter?

Also what about the oil pressure bypass in the oil pan?

Oil filter was an Acdelco, but was replaced with a Mobile1 filter between new and new-new oil pump.

The Oil pan pressure release valve was replaced when I had the engine out in the summer. So I guess another suspect for a faulty part.

 

[01FormulaTA]

I replaced the pick up tube because it was cheap and easy to replace with the engine out. I also did it to help ensure I had a 100% clean pick up screen, and to make sure I had the right o-ring.

Hmmmm I don't recall o-rings on the valley cover, and I didn't snap any pics of it when I had it off. Although I know my valley cover is different( ie flat) since I dont have afm. I think you may be confused, I know they later added afm to the L92 without other modifications, but I dont think my engine has any of the afm components in it. If there are o-rings on the valley cover that I missed, i could see that being a problem since the main gasket is new, the old o-rings would probably not make a good seal now. Sounds like a good thing to check since I would need to pull the intake and valley cover to install my lift plate if I end up pulling the motor again anyways.

Not confused at all....it’s a fact some early 07 L92s had AFM components even though they didn’t have AFM active...the 6.2s that had AFM active are the L99(Camaro) and L94(2010+ Escalade and Denali SUV)...I bet if you went back to your original pump and pickup tube you would be back to normal oil pressure...and the Valley Cover has 8 O-Rings that block off the AFM oil ports(present on all Gen 4 LS), if they aren’t sealing this could also be part of your problem

 

[01FormulaTA]

 

[01FormulaTA]

Also the fact you mention you replaced the oil pressure relief valve is another indicator your engine may have AFM components...that valve is used to bypass excess oil pumped by the high-volume oil pump when AFM is not active....if you install a standard volume pump without deleting the oil pressure relief valve it could cause low oil pressure

 

[01FormulaTA]

When comparing your valley cover to the pic below does it resemble the one on the left(AFM Style) or right(no AFM)??