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Discussion Starter · #1 ·
Truck is a 2000 Silverado 5.3. My oil pressure while idling is always at 40 or either just one notch below 40. I was driving today and while on the interstate I noticed my oil pressure was low (at 40 while at 2000rpm) when it's normally at like 60 at that rpm. When I would stop and my engine would idle at the normal 500rpm the psi would be at 22-24. This worries me a lot so I drove easy until I got to my destination. When I arrived I checked my oil level, it was perfect. I then cranked my truck up again, oil level was at 40 like normal. When I got back to my truck an hour later to head home I cranked it and it was at 40 as well so perfectly normal. After a few minutes of driving it started going back down again. The lowest it'll be is 22 while idling. Anyone know what's causing this and how I can fix it?
 

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Discussion Starter · #3 ·
Also not sure if this has to do with anything but I did get my truck tuned a couple days ago and yesterday I washed my engine. It wouldn't crank until it was dried off so I guess a wire or something got wet but it cranked up once dry and runs normal.
 

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Discussion Starter · #6 ·
ElReeso said:
on a 2008 but process is similar on yours:


and 98-02 sending unit:

I'll try replacing the sensor first. Seems pretty quick and easy. What about the screen underneath? How would I remove it and clean it out? Also I read somewhere else about someone just leaving the screen out permanently. Could I just do that?
 

馃弲TOTM
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I have the same problem and will change the sensor first.. ordered the O-Ring too because its only $1.50 and I don麓t want to wait on it if the sensor method fails. I don麓t have a screen in there (got a 6.0L) and I dont think you have.. just noticed MY2000 should have no AFM. No AFM means no Screen if I麓m correct..
 

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Discussion Starter · #8 ·
ElReeso said:
I have the same problem and will change the sensor first.. ordered the O-Ring too because its only $1.50 and I don麓t want to wait on it if the sensor method fails. I don麓t have a screen in there (got a 6.0L) and I dont think you have.. just noticed MY2000 should have no AFM. No AFM means no Screen if I麓m correct..
How would I know if it has a screen? Is it visible? I can just pull it out with my fingers?
 

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Discussion Starter · #9 ·
Ok so I got a shop to do it. They pulled the old one out and apparently it was broken as shown in the pics (I'm not sure if it's been like this or if he just broke in when trying to remove it). I bought a replacement one at the auto Parts store and it looked different than the original one. The ones at the store have longer threading and the little black dot in the center is shallow instead of flush. I tried to find and ac Delco one but nobody carried it so I just went with this one. Is that going to make a difference? After it was installed it did the same exact thing. Oil pressure was normal at first then after driving around it went down. I'm not sure if it's because this one was different or if it's something else. Should I get an ac delco one instead?
 

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It is normal for your oil pressure to drop some after driving for a while,
since the oil thins out the hotter it gets.

I have had several trucks that only held 20 psi hot idle and around 35 (hot) on the road.

I used to worry about it, but now I have an F-grade for a daily driver,
and furd is good enough to not put numbers on the gauge,
so I don't even know what hell my oil pressure is now ;)

Joe
 

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Discussion Starter · #12 ·
JSDelaware said:
It is normal for your oil pressure to drop some after driving for a while,
since the oil thins out the hotter it gets.

I have had several trucks that only held 20 psi hot idle and around 35 (hot) on the road.

I used to worry about it, but now I have an F-grade for a daily driver,
and furd is good enough to not put numbers on the gauge,
so I don't even know what hell my oil pressure is now ;)

Joe
No it's definitely not supposed to be like this it's never been lower than one notch below 40. I need to get it fixed ASAP.
 

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Please keep us updated, I had this problem not long ago. It just seemed to happen all of a sudden I only had 40 psi while driving down the highway and 25 at idle. I changed the oil and filter from the usual Amsoil I was using to Schaeffer's and a Mobil 1 filter and now it's back to normal so far.
 

馃弲TOTM
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I would get an ACDelco one just to verify it is 100% correct. May not solve the issue as I stated but then you can really identify its not the sending unit.
Although I have never seen a sending unit damaged that much.. I guess the mechanic screwed it up when removing..

New Oil with a quality filter can solve this issue too but its depending on what you use now. If you use quality oil with quality filter by now the issue should be elsewhere.

And no screen for you because you got no AFM. Be happy about it ;)

I would suggest:
Change sending unit to AcDelco
Oil Change with quality oil and quality filter if not done already
Drive it to see if something is changing..

If the problem still occurs you may be looking at replacing that O-Ring. If Money doesn麓t matter that much you can get a whole new pickup tube and a new Oil pump just to be 100% sure..
 

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Discussion Starter · #15 ·
ElReeso said:
I would get an ACDelco one just to verify it is 100% correct. May not solve the issue as I stated but then you can really identify its not the sending unit.
Although I have never seen a sending unit damaged that much.. I guess the mechanic screwed it up when removing..

New Oil with a quality filter can solve this issue too but its depending on what you use now. If you use quality oil with quality filter by now the issue should be elsewhere.

And no screen for you because you got no AFM. Be happy about it ;)

I would suggest:
Change sending unit to AcDelco
Oil Change with quality oil and quality filter if not done already
Drive it to see if something is changing..

If the problem still occurs you may be looking at replacing that O-Ring. If Money doesn麓t matter that much you can get a whole new pickup tube and a new Oil pump just to be 100% sure..
Well if it is the oil and oil filter that's causing this then wouldn't it have done it when I first changed the oil? I've been driving 500 miles since my last oil change so I highly doubt it's that. Just gonna get the ac delco one to be sure it's not that. If that doesn't fix it then I guess just replace the oil pump.
 

馃弲TOTM
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Yup right with that! Just missed that you did an Oil Change recently.

When you spening money on the Oil Pump then replace the O-Ring at least. Would be a bummer when you spend big money for the pump while a $1.50 O-Ring is failing..
 

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22-24 psi is not low oil pressure. My 2017, 2015, and 2008 would both stay around that when the engines really hot at idle. As long as it goes back to 40psi while cruising you're fine.

Now if your oil pressure warning light came on them you worry.

Sent from my iPhone using Tapatalk
 

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Discussion Starter · #18 ·
ElReeso said:
Yup right with that! Just missed that you did an Oil Change recently.

When you spening money on the Oil Pump then replace the O-Ring at least. Would be a bummer when you spend big money for the pump while a $1.50 O-Ring is failing..
Well since the o ring is a common problem for these pumps, can I buy a better higher quality o ring somewhere instead of the stock one? I don't want this problem resurfacing again later on because of the junk o ring.
 

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Discussion Starter · #19 ·
ferraiolo1 said:
22-24 psi is not low oil pressure. My 2017, 2015, and 2008 would both stay around that when the engines really hot at idle. As long as it goes back to 40psi while cruising you're fine.

Now if your oil pressure warning light came on them you worry.

Sent from my iPhone using Tapatalk
Yeah if I were you I'd get that checked out. It's supposed to be at 40 while idling and 60 cruising. It probably won't hurt anything but I would make sure it's running at the right pressure at all times to be safe.
 
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