I had the low oil warning at idle but my truck was also rattling from the engine verifying that there was actually low oil pressure and not just a bad sensor, Before tearing into it I ordered oil pump timing chain and all associated gaskets, when i tore it down I found a brittle o-ring at the oil pump pickup to be the culprit, after repairing this, oil pressure was back to normal and even my rattle at cold startup was gone, this was my situation
Wesyder thanks for your response, the weird thing is, my lifters aren't knocking at all! there's no audio signs of that, i do however hear a manifold leak at startup but that goes away with 20 seconds or so but that sound i've been hearing since a year after i bought it. Did you have to drop the front axle? to get to your oil pump pickup tube? My buddy who's a mechanic said there's other ways, but the safest is to remove everything that will be in the pan's way to not lose a screw or something like that.
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I had the same problem. Low oil pressure and ticking lifters, definetly a sign.
With wesyders advise (like above) I too resolved the issue by replacing the oil pick up tube o-ring. I also replaced the oil pump and timing gear set.
Comparing the new timing gear set against the original with almost 200k on them, I really did not need to replace.
If you are DIYing if you have all wheel drive your looking at about 8 hours IIRC. Two wheel drive vehicles are much easier with shorter replacement time.
I guess you answered my question, all that stuff has to be removed if this is indeed my issue, thanks Jnresv.
Anyone else have any ideas?
I wasn't clear on my original post but these is my situation. ..
1. Low oil pressure at Idle about 3 PSI (Chiming sound)
2. 15 PSI at city driving, and of course dropping to 3 PSI when stopped.
3. 20 PSI at 55 MPH
4. No valvetrain noise.
5. Replaced 5 w 30 Mobil one oil (Synthetic) and Fram filter, always had been used, with 10w30 Royal Purple (Synthetic), and AC delco filter and nothing changed.
I'm thinking something is clogged somewhere. is there a way to vacuum oil out from somewhere where big particles also can be sucked out?
Can the oil cooler cause this?