Low oil pressure

[Walchit]

I really don't wanna pull the pan again, I'm about to do this motor flush, and change the sending unit. I have been randomly getting good oil pressure about half the time now. This truck was supposed to have a super low mile rebuilt engine, but the pan looked like that.
So I doubt it has the 7k he said, or the lifetime warranty he didn't have paperwork for, .

Oh and now I randomly get "check engine oil level" in the message center... I barely wiped off that sensor/switch thing when I had the pan off, now I'm wondering if I shouldn't have touched it, or if I should have actually cleaned it. And you have me wondering about the spring too.

What is your pressure at idle?
I'm right around 20 most of the time, all of my buddies trucks idle at 40, and wot at 80 lol

 

[Tonyrodz]

I really don't wanna pull the pan again, I'm about to do this motor flush, and change the sending unit. I have been randomly getting good oil pressure about half the time now. This truck was supposed to have a super low mile rebuilt engine, but the pan looked like that.
So I doubt it has the 7k he said, or the lifetime warranty he didn't have paperwork for, .

Oh and now I randomly get "check engine oil level" in the message center... I barely wiped off that sensor/switch thing when I had the pan off, now I'm wondering if I shouldn't have touched it, or if I should have actually cleaned it. And you have me wondering about the spring too.

What is your pressure at idle?
I'm right around 20 most of the time, all of my buddies trucks idle at 40, and wot at 80 lol

Are you sure the soil sensor is good?

 

[Walchit]

No, but I figured the flush might gunk it up, so I was gonna do it then if it didn't fix it I was gonna check the sensor. It didn't sound like it was very fun to get off of there. I have fat hands lol

 

[rbrt43]

I purchased a 2009 Tahoe SSV in April. It has 95K miles on it. A few weeks ago I was driving down the highway and I got a check engine light, then a couple of minutes later a warning that said low oil pressure stop engine, so I stopped as soon as was safe to do so. I have since had the oil pump and pickup tube replaced with a melling high volume pump and decided to go with a slightly higher viscosity oil (10-40 as opposed to 5-20) using Valvoline High Mileage oil and a quart of Lucas oil stabilizer. When I start it and it is cool outside (doesn't get cold this time of year in Texas) startup pressure is about 40. I drive it for about 5 miles at 75 running about 2k rpm and the pressure drops to about 20. I stop it and at an idle pressure is around 5 to 7 psi according to the gauge. I have been fighting with this for almost a month and nothing I have done (replaced pump, replaced the pickup tube making sure to use the correct o-ring, changed the sensor, even changed the oil a couple of times) has done any good. I am just looking for further ideas. Right now the mechanic believes the new pump may be bad and is in the process of removing it so that it can be exchanged.

 

[Brandon2489]

I purchased a 2009 Tahoe SSV in April. It has 95K miles on it. A few weeks ago I was driving down the highway and I got a check engine light, then a couple of minutes later a warning that said low oil pressure stop engine, so I stopped as soon as was safe to do so. I have since had the oil pump and pickup tube replaced with a melling high volume pump and decided to go with a slightly higher viscosity oil (10-40 as opposed to 5-20) using Valvoline High Mileage oil and a quart of Lucas oil stabilizer. When I start it and it is cool outside (doesn't get cold this time of year in Texas) startup pressure is about 40. I drive it for about 5 miles at 75 running about 2k rpm and the pressure drops to about 20. I stop it and at an idle pressure is around 5 to 7 psi according to the gauge. I have been fighting with this for almost a month and nothing I have done (replaced pump, replaced the pickup tube making sure to use the correct o-ring, changed the sensor, even changed the oil a couple of times) has done any good. I am just looking for further ideas. Right now the mechanic believes the new pump may be bad and is in the process of removing it so that it can be exchanged.

Has anyone put a mechanical gauge on your truck to verify oil pressure? What oil filter are you using?

 

[rbrt43]

Actually, they haven't. I was using a Fram Extraguard, however, after reading some of the information on this thread I purchased a K&N for when it goes back together with a different new oil pump

 

[Brandon2489]

For what it's worth I used to run the AcDelco P48E filters but after one of my oil changes I started experiencing low oil pressure. It never got 6-7 pdinat ifle more like 15-20. I kept the old oil in since it had less than 3000 miles on it and to only change one variable at a time. I changed to a K&N HP2011 oil filter and everything returned to normal. I have a new screen and oil pressure sending unit ready to be installed but the filter fixed the problem. I would put a mechanical gauge on it and verify oil pressure before pulling the pan and pump again. Also fill with 2 quarts extra of oil and raise the rear end about a foot and let it idle. See what the pressure is then. If it's good then your pickup tube oring is bad. Do this with a mechanical gauge still hooked up. like I said it sounds like the only thing that hasn't been changed is your oil filter so that would be the plane i would start first. It is the easiest thing to change. You don't even need to drain the oil. Just poke a hole in the bottom of the filter with an awl and let the filter drain. Maybe half a quart. Fill new oil filter with oil and put back on. Check progress. Let us know.

 

[rbrt43]

When I posted this the new pump had already been removed. The new pump came with a new pickup tube and o-ring. My mechanic is supposed to have it changed out in the next day or so and hopefully it will fix the issue. He has drained the oil several times since this happened and the last time, even though I had only driven the vehicle about 10 miles and it had been running for about 30 minutes he said that the oil was very black and dirty so this time I bought a can of Seafoam along with my new oil and now the K&N filter. I will post the results once he is finished with it.

 

[avalonandl]

Just as an FYI I use the Wix 57045 on my 2012 6.2 Denali. This has a DIFFERENT size thread but a 12-15 psi bypass so it always has that min. PSI.

 

[Mudsport96]

I run the delco 61e on both of my 5.3s. It is the long version of the recommended filter and never have pressure drop below what i consider normal for my vehicles.