88 k1500 with 57k miles low oil pressure

TrevorAnthony

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Hey guys, I was curious about correct oil pressure numbers because I have heard the stock ones aren't too accurate. So I bought an intellitronix digital gauge for around $70 and installed it where the stock one is on the side of the block. it reads about 22 on cold start, then once it warms up goes from around 2-10 which is a bit concerning. It's a bit odd since it's pretty low miles. thought I'd see what you guys had to say. Thx
 

jjester6000

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Hey guys, I was curious about correct oil pressure numbers because I have heard the stock ones aren't too accurate. So I bought an intellitronix digital gauge for around $70 and installed it where the stock one is on the side of the block. it reads about 22 on cold start, then once it warms up goes from around 2-10 which is a bit concerning. It's a bit odd since it's pretty low miles. thought I'd see what you guys had to say. Thx
My '98 Burb will get as low as 20lbs when idling, and its got 308k on the original motor.

2-10psi at idle is pretty low, and would concern me. What sort of oil are you running? I'd be running at least 10w40 with Lucas if I saw numbers like that.

This may be from a bad oil pump, but more likely from worn main/rod bearings. In that case I'd go with thicker oil and it'll probably run for quite a few more miles.

If you ever have the oil pan off, I'd suggest doing the rod/main bearings while you're in there (they're not too difficult to do while in the vehicle, the biggest thing you need to do is drop the front differential).
 

Schurkey

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I bought an intellitronix digital gauge for around $70 and installed it where the stock one is on the side of the block.
You installed the gauge on the side of the block???

Or you installed the sending unit on the side of the block? Or you installed the gauge tubing for a mechanical gauge on the side of the block?

Have you tested the gauge to see if it's accurate? In my driveway, I'd turn down the pressure on my air compressor to ~60 psi, and connect the sending unit to the air hose. See if the oil pressure gauge matches the gauge on my pressure regulator.

Or connect the oil pressure gauge to a known-good engine, see if it still reads low.

Realistically, 22 psi on cold start is WAY LOW. My '88 pegs the gauge when first started (60+ psi) but shows about 15-ish psi at hot idle in-gear.
 

TrevorAnthony

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My '98 Burb will get as low as 20lbs when idling, and its got 308k on the original motor.

2-10psi at idle is pretty low, and would concern me. What sort of oil are you running? I'd be running at least 10w40 with Lucas if I saw numbers like that.

This may be from a bad oil pump, but more likely from worn main/rod bearings. In that case I'd go with thicker oil and it'll probably run for quite a few more miles.

If you ever have the oil pan off, I'd suggest doing the rod/main bearings while you're in there (they're not too difficult to do while in the vehicle, the biggest thing you need to do is drop the front differential).
I just changed the oil yesterday with mobil 10-30, and a Wix filter, I was hoping the number would go up a bit.
 

TrevorAnthony

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You installed the gauge on the side of the block???

Or you installed the sending unit on the side of the block? Or you installed the gauge tubing for a mechanical gauge on the side of the block?

Have you tested the gauge to see if it's accurate? In my driveway, I'd turn down the pressure on my air compressor to ~60 psi, and connect the sending unit to the air hose. See if the oil pressure gauge matches the gauge on my pressure regulator.

Or connect the oil pressure gauge to a known-good engine, see if it still reads low.

Realistically, 22 psi on cold start is WAY LOW. My '88 pegs the gauge when first started (60+ psi) but shows about 15-ish psi at hot idle in-gear.
I installed the sending unit in on the side of the block, I had to use a 1/4 npt to 1/8 npt adapter to make it work, but from what I can tell everything is wired correctly. I did the valve stem bushings a couple of months ago, and the top end looks pretty mint, I've yet to take the oil pan off, but I'm curious to see what's in there. although in the head on the back drain hole toward the firewall, there was a Texaco motor oil quart seal that was blocking the drain hole, don't know if that could affect the pump starving it in any way and wearing it out.
 

GMCTRUCKS

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What about a straight weight or heavier weight oil try it and let us know.

Low pressure low miles it should have good pressure maybe the lower engine needs rebuilding but WHY
 

dave s

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Like was mentioned, before I got too concerned I would make sure that gauge was accurate.
 
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