Is this oil pressure normal?

[Paul Brambilla]

07 Yukon Denali 157k miles

When warm and at idle, pressure drops pretty low. Sometimes when I get off the highway the traction control / stabilitrac error message comes on, then if I get back up to speed it often goes away.

I've seen people recommend changing out the oil pickup o ring. Could it be that simple or is there something else going on?

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[Doubeleive]

i'd have to say that's abnormally low oil pressure and your traction control issue may be a wheel hub sensor or a bad hub, a scanner capable of reading live data would be useful for the traction control problem.

the oil pump o-ring is a common issue as is the sensor and screen, a oil pressure test from the pump output would likely point you in the correct direction to proceed

 

[Derick]

That does seem low but not far off of what mine is doing

I saw another picture of a suburban at idle and it was about the same. Ive got a new sensor and it has never bottomed out so I think it's OK at this rate.

 

[swathdiver]

Do the simple things first, like change the oil filter. Then check to see if your motor was one of the ones with AFM hardware and change the pickup tube screen under the oil pressure sensor if you have it. If not, go to step 3 and consider replacing that o-ring.

 

[Sparky75013]

I had a very similar occurrence. I even had like a lifter knock that would occur at about 3000 RPM, but that was rare. I replaced the O-ring, and my pressure returned to normal.

 

[Charles Land]

07 Yukon Denali 157k miles

When warm and at idle, pressure drops pretty low. Sometimes when I get off the highway the traction control / stabilitrac error message comes on, then if I get back up to speed it often goes away.

I've seen people recommend changing out the oil pickup o ring. Could it be that simple or is there something else going on?

I had the same problem with my 01 surburban. In addition to low pressure at idle, the pressure needle would jump around a bit at idle and slightly higher iRPMs. I assume the failed O ring was causing the oil pump to suck some air and thus the eratic pressure indication. Replaced the oil ring and problem solved. A $1 part and a couple hours work.

Sent from my PH-1 using Tapatalk

07 Yukon Denali 157k miles

When warm and at idle, pressure drops pretty low. Sometimes when I get off the highway the traction control / stabilitrac error message comes on, then if I get back up to speed it often goes away.

I've seen people recommend changing out the oil pickup o ring. Could it be that simple or is there something else going on?

Sent from my PH-1 using Tapatalk

 

[67RS427]

Don't think you'll get lucky with a cheap easy fix on that one... Run a thicker oil for now, 5w-40 or 10w-40. Same issue my 07 Denali had with the same mileage. I ended up building a new motor for it. Literally just tore down my original 6.2L motor last week and found the main and rod bearings were fine however the CAM bearings were down to the copper core. The rest of the motor looked fine but it certainly explained the low oil pressure. Some of those early engines were assembled with loose/sloppy main clearances that could cause it but I doubt that's your issue. Good luck!

 

[Paul Brambilla]

Thanks for all the replies. I finally ended up taking it into a shop. They did some analysis and confirmed the sensor is ok, and that mine doesn't have a screen. At this point I strongly suggested they simply replace the o-ring, but the guy looked at me like I was crazy. He told me he was positive that there's no way it's just the o-ring and that I needed a completely new oil pump. The quote was about $2k. I kept suggesting the o-ring but he insisted that wasn't the issue.

I guess on the way to the oil pump, you'll have an opportunity to inspect the o-ring but at this point I wasn't super comfortable with this guy so I just decided to cut my losses and leave.

I realize it's a PITA to get to the o-ring, but I'm starting to wonder if maybe I shouldn't just replace the entire oil pump just to be safe. Otherwise, if I have the entire thing torn down/put back together and it turns out is is the pump, I'm just going to have to tear it all back down again.

Is this guy right and should I just replace the pump and o-ring? Or should I find myself another mechanic? I wish I had means to do this myself, but this goes a bit beyond what I'm comfortable with.

 

[SnowDrifter]

I did pump and o-ring when I did mine. My reasoning was this:

If I need to drop the pan, then I should to the front cover too. The gaskets mate with eachother and it makes sens to replace them both. I would have done the rear cover too but the ROI for labor to drop the trans wasn't there.

Then, I figured, if I have front cover off: Oil pump is just bolts at that point. Replace it and be done. I reckon it was worth my while as there was some wear on the old one. The gearotor types don't last forever!



Lending a different perspective: There's a good chance the recommendation for the oil pump was for liability. For better or for worse, it's how a lot of shops need to function.

Let me propose a scenario: Shop replaces o-ring. Doesn't fix issue. Engine blows up. Shop now liable for not catching oil pump on account of being the last ones to touch it. You could argue the ethics of it but regardless, the courts tend to favor the consumer in cases such as these. That's why it's rare to see a shop do partial work, even if possible, just due to liability. i.e. they won't replace a leaky caliper on one side. They do both. And pads. And rotors. Or they won't just bearing slap and hone an engine on the cheap, it's a full and proper rebuild. etc etc.

Hell... Think of the number of times quick lube places get in trouble for blowing up an engine. Meanwhile the customer drives it with the oil light screaming at them and the radio turned up to hide the noise as clatter turns to knock


Yes I know you get the occasional ma and pa shop who does the minimum to your benefit. But most don't function that way.

 

[iamdub]

All you have to do to check the O-ring is overfill the oil pan by 2 or 3 quarts to get the oil level higher than the O-ring. I think it takes 2 quarts. You don't wanna drive it like this but it's a quick and easy test and better than tearing into it only to find it's not the problem.

First thing's first: Confirm the actual pressure. The gauge and PCM are going off of what the pressure sensor is reporting and it could be faulty. Use a mechanical gauge to determine the actual pressure. If it is in fact low, then it's either a weak pump, leaking pickup tube O-ring, too loose of tolerances (excessive bearing wear), a clog (sludge buildup blocking the pickup tube (least likely), failed pressure relief valve in the oil filter or cam retainer plate gasket leaking. Everything but the sensor and filter involves opening up the motor to repair and everything puts you in the "while I'm here I may as well..." category: If it's the O-ring, you may as well replace the pump, too. If you replace the pump, it comes with a new O-ring but you may as well replace the timing set and cam retainer, too. If you pull the timing set, you may as well pull the cam to inspect and/or replace the bearings...

But, to at least diagnose the cause, start at the beginning by confirming the pressure then ruling out the cheap and easy stuff.