The gauge is so low because that's the way Chevys are. I remember a dually truck with a 350ci or a 460ci back in the day and it was the same, oil pressure very low. Then I had Suburban also with the 5.7l (350ci) and same. Right now I have a Chevy Express 6.0L and the engine always has low pressure. It runs like a champ and it doesn't burn oil at all. It doesn't even dirties the oil. The guy who you bought it from was trying to tell you don't mess with it. That's what he meant by "it's always been low."
Having same issue. o bought a 06 2500 van 70,000 miles. first time i started it 0 oil pressure. after warm up 20 psi . if i gave it gas it would go to 36 psi. i bought it anyway because the motor ran so smooth and plenty of power on ticking. after watching YT videos i was convinced that it was o ring and oil pump. No shops wanted to do it i figured about 2000- 2500.00 i was planning to do it myself and also replace water pump . but after watching your video i think imma just let it Ride. thanks for posting this video.
@@toenails. An engine builder I know gets them in all the time. All of them have the same problem. Cam bearing is gone. Usually number 3 or one. Mostly gen 3 and some gen 4. Maybe the owners didn't change their oil. Happens on the 5.3 as well but on those it's usually maintenance issues.
The old style GM sending unit is a simple variable resistor so you can attach a decade box from signal wire to ground, then adjust resistance and see what the gauge shows. As I recall Alldata have specs for what the stepper motor gauge in the cluster should show at 100 ohms, etc.
I have a 2005 z71 5.3 Tahoe with over 300,000 miles on her that had the same low oil pressure, I replaced the sensor which also did not solve it so I dropped the oil pan and it turned out to be my pickup tube O-ring, it was hard and squared up. What burns my chaps is that I had my mechanic replace my oi pan gasket the year before and he did not change the o-ring at that time but said he did, when I showed him the proof he blamed his helper. It is now running over 40 psi cold and plus 50psi at higher RPMs, when it was running low (under 20 psi) I was getting a light lifter tick that would come and go and on occasions I would get a low oil pressure warning when the engine was warm and I was stopped. The Tahoe is now running better then it has ever has and she does not burn a drop of oil. I ran strictly mobile one synthetic oil and I was NOT good at keeping up on her oil changes when she was young, I stretched some of them pretty far, but I am much better now and I have been short cycling the intervals by about 15% to be sure she is happy. Oh I also replaced my oil pump when I changed the pickup tube o-ring just because I was there.
What does the gauge inside say at higher idle if it mirrors your gauge but just 20 psi under maybe the cluster got removed and they didn’t put the arm on the gauge correct
I had a ‘95 k2500 that would always show low voltage at the dash gauge. I would periodically check the output of the alternator with a meter. I just took it as old inaccurate gauges.
I actually did . The scanner says it has low oil pressure also , so the reading will be skewed . I think it's the pcm honestly. But I'm not too worried, I'll mount an aftermarket gauge on it if the buyer is worried
Is the oil pickup tube with the $3 oring before or after this plug you've got the gage on? In simple terms would you get a different reading on tour guage if plugged into the back. Just bought an 09 and they said they did sensor and pump and acted quality. I would like my check engine light to go away so I could use remote start.
6.0 engines do not have a screen if correct. I think the 4.8, 5.3 and AFM motors do have them. Cannot recall why maybe debris buildup or some strange reason regulates pressure. I removed the screen in the above said motors and never saw anything unusual to require replacement. Strange design if you ask me.
Sometimes those stepper motors with the plastic gears on gauge break or slip like a timing chain. May have skipped a tooth that has been my assumption or like you said with ecm/pcm.
so I had a 2003 quadersteer oil pressure cold was over 60 .an hour drive it drop to close to zero. under warranty, they changed the oil pump oil sensor still the same ended up being the speedo cluster yes your truck is newer but gm has had problems with their clusters since ate
Maybe I’m wrong but if there was any blockage in the galley from the pump to the sender port could it not read a higher pressure on the lower port that’s coming right off the pump than the port on the top back of the block which has to go through the galleys and filter before reaching that port
I have this same issue with a 03 ford ranger edge 3.0. Oil pressure gauge needle has jumped over the knob. When coming to a stop at operating temperature the check gage light will come on. Has been checked and the mechanic says I have oil pressure and oil pressure is fine. The new oil pressure sensor didn't change anything. He recommended a new instrument cluster. You think pcm?
Ive delt with this issue a few times on Ford Ranger's. If you take the cluster out and pop the lens off , you can rotate the needle back around and it should go back to its resting position. It won't hurt anything to just keep rotating away from the stop to the "low" point . It should actually free flow there after you pass a certain point
I actually had same situation on an 04 6.0 in a 2500. My question is will the adapter for manual oil pressure gauge also work in the oil pressure switch hole? I wanted to go to a manual gauge and did so but I actually cut the top off the switch down to the metal base then drilled and tapped it for 1/8 pipe thread and then I had my manual gauge.
