Yep, another oil pressure issue
01-16-2016, 03:04 PM
#1
Yep, another oil pressure issue This is a 2002 2500 with LQ4. A company truck that I bought for an employee to drive. Has over 290k. Actually runs pretty smooth with plenty of power. Sooo.
Today had been going just fine. Fixed the leak at my heater core to hose location and started the truck to make sure the leak was fixed. Noticed it was ticking louder than a normal high mileage tick. Looked at stock pressure gauge and its on the bottom. Zero pressure. Shut it off, check the oil, start it back up. No pressure. Raise the rpm a little and the gauge kind of bumps its way to about 25psi and the tick gets much more quiet. Sounds like a lifter ticking. Let it go back to idle and the pressure holds for a few seconds, then kind of starts to stumble and drops to zero, tick gets loud again. So yes, the pressure is down, its not just the stock crappy gauge.
I really don't want to pull this for a rebuild. I know it wouldn't hurt. But I will be gone all next week and my employee needs a truck for work. I have read about the ATF being added which helps swell the o-ring seal in case its dry and cracked. It has new 15w40 in it now. Just changed it about a week ago. Oil looks clean and clear. It doesn't appear to be a sludge issue in the pan. The oil would get dirty again pretty quickly.
Does this sound like an o-ring issue? Ideas? If I try the ATF trick, which one are you guys using?
Today had been going just fine. Fixed the leak at my heater core to hose location and started the truck to make sure the leak was fixed. Noticed it was ticking louder than a normal high mileage tick. Looked at stock pressure gauge and its on the bottom. Zero pressure. Shut it off, check the oil, start it back up. No pressure. Raise the rpm a little and the gauge kind of bumps its way to about 25psi and the tick gets much more quiet. Sounds like a lifter ticking. Let it go back to idle and the pressure holds for a few seconds, then kind of starts to stumble and drops to zero, tick gets loud again. So yes, the pressure is down, its not just the stock crappy gauge.
I really don't want to pull this for a rebuild. I know it wouldn't hurt. But I will be gone all next week and my employee needs a truck for work. I have read about the ATF being added which helps swell the o-ring seal in case its dry and cracked. It has new 15w40 in it now. Just changed it about a week ago. Oil looks clean and clear. It doesn't appear to be a sludge issue in the pan. The oil would get dirty again pretty quickly.
Does this sound like an o-ring issue? Ideas? If I try the ATF trick, which one are you guys using?
01-16-2016, 03:10 PM
#2
Pickup tube O ring or it lost a cam bearing. My LQ4 was sitting at zip near idle and would jump to about 10 PSI at 2K RPM. My cam retainer plate gasket was blown out and the cam bearing was resting comfortably on the camshaft lobe.
Drain the oil and look for copper sparkles, that will tell you if the cam bearing spun.
Drain the oil and look for copper sparkles, that will tell you if the cam bearing spun.
01-16-2016, 03:48 PM
#3
Yea I know all about checking for metal ect. I'm just new to the GenIII pickup o-ring issues. I have heard several things can go wrong with them.
I went ahead and added 1qt of ATF to it. Drained a little oil so not to overfill the pan. And heres what confuses me a little more. Started it up and it went right to 35psi. Let it idle and it dropped after about 5 seconds. Went ahead and drove it and it ran right at 40psi the whole time. When at a stop and at idle, it would come down again to near or at 0. Give it a little gas and it jumped right up. Drove it for about 5 miles just to get the water to temp or close. Sat idle in my drive for a few minutes and the pressure went from 35 down to 30 and stayed. The gauge does have a little movement before it comes down. Kind of like a bad actor getting shot in a bad movie and then dies. LOL
I'm going to see what the trany fluid does to help it if anything. I'll drain the oil later sometime to see if there is anything in it and if there is then I will cut the filter open and check that too for larger pieces.
I went ahead and added 1qt of ATF to it. Drained a little oil so not to overfill the pan. And heres what confuses me a little more. Started it up and it went right to 35psi. Let it idle and it dropped after about 5 seconds. Went ahead and drove it and it ran right at 40psi the whole time. When at a stop and at idle, it would come down again to near or at 0. Give it a little gas and it jumped right up. Drove it for about 5 miles just to get the water to temp or close. Sat idle in my drive for a few minutes and the pressure went from 35 down to 30 and stayed. The gauge does have a little movement before it comes down. Kind of like a bad actor getting shot in a bad movie and then dies. LOL
I'm going to see what the trany fluid does to help it if anything. I'll drain the oil later sometime to see if there is anything in it and if there is then I will cut the filter open and check that too for larger pieces.
01-16-2016, 05:13 PM
#5
Go to walmart and buy some TransX, that will swell the seal up until you can replace it. Put 3-4 ozs in. IOt takes some time for the oring to swell back up, its not instant. Good Luck
Trending Topics
01-18-2016, 11:11 AM
#12
Yea, the outside edge and inside edges were flat, not round anymore. So this allows air to get sucked in.
You would think that GM could have designed this better. Maybe just a flat plate with a gasket. O-rings just get hard and go bad with heat and oil.
You would think that GM could have designed this better. Maybe just a flat plate with a gasket. O-rings just get hard and go bad with heat and oil.
01-18-2016, 07:48 PM
#14
Ever wonder why thee are virtually zero failures on factory assembled engines? Why these o-ring failures never seem to occur until someone replacing parts? A lot of peeps don't realize there is more than one o-ring size and what you need depends on what p/u tube you're using. I'm pretty sure this is the root cause of most of these so-called o-ring failures. Some tubes have one "step" while others have multiple steps, and the o-ring you use must fit/seal on the correct step. There was a really good write-up here a couple years ago, if you're industrious with the search feature, you might find it...
01-19-2016, 11:08 AM
#17
01-19-2016, 11:18 AM
#18
Yea, just like everything sold, it can fail at anytime. I sold brand new Ford trucks when they came out with the new 6.0 diesel. I had one that didn't make it 5 miles when the owner took deliver. Engine blew up.
And stuff like this is why I am about to buy my wife a new vehicle and will most likely go to a dealer and manufacture that have a free lifetime powertrain warranty. A lot of them around my area are doing this now. I wish GM would. I think they will have to sooner than later though or else they will be losing potential customers to the other makes.
And stuff like this is why I am about to buy my wife a new vehicle and will most likely go to a dealer and manufacture that have a free lifetime powertrain warranty. A lot of them around my area are doing this now. I wish GM would. I think they will have to sooner than later though or else they will be losing potential customers to the other makes.
01-19-2016, 01:40 PM
#19
I had the same issue in my 03 2500 with 175k on it, very delayed pressure on startup and only 20psi cold idle. Replaced it with the GM red o-ring and raises to 40psi cold startup and slight tick is gone.
I was VERY worried that it was a bearing...SO happy it was as simple as the o-ring.
I was VERY worried that it was a bearing...SO happy it was as simple as the o-ring.
01-19-2016, 05:14 PM
#20
Yea, just like everything sold, it can fail at anytime. I sold brand new Ford trucks when they came out with the new 6.0 diesel. I had one that didn't make it 5 miles when the owner took deliver. Engine blew up.
And stuff like this is why I am about to buy my wife a new vehicle and will most likely go to a dealer and manufacture that have a free lifetime powertrain warranty. A lot of them around my area are doing this now. I wish GM would. I think they will have to sooner than later though or else they will be losing potential customers to the other makes.
And stuff like this is why I am about to buy my wife a new vehicle and will most likely go to a dealer and manufacture that have a free lifetime powertrain warranty. A lot of them around my area are doing this now. I wish GM would. I think they will have to sooner than later though or else they will be losing potential customers to the other makes.
