ok driving home from work today my oil pressure would drop to about 25<35 at idle but when driving or rev it up and it would do about 40+ which i think is more normal. i have never had the pressure that low at idle it is always been around 40-45 at idle. is this normal or do i have a problem. i feel i might be overthinking it because it idles smooth and power is the same and everything seems normal besides that. thanks for all input

 

I have the same problem. If I am cruising around at 1500rpm's or so it will stay around 40psi then. Although when I do go WOT it looks as though it stays just shy of 60psi.

 

anybody have any ideas

 

so is this normal cause nobody is responding???????

 

Sounds goods for an engine at normal operating temperature. My car was the same way since day one without a problem. Just make sure the pressure does not drop at WOT. I always used 6.5 quarts of oil to prevent this from happening.

BTW - How many miles are on the engine?

 

what weight oil do you guys run? i run 10w40 and mine stays at least at 40psi when hot at idle. if you are running 5w20 or 5w30 or something like that it get thinner at operating temp as compared to my 10w40. just a thought.

 

I use mobile 1 15/50. I just got used to running that from when I was out in Vegas, and have never switched to anything else.

 

I use 5 quarts of 10W-30 and 1 quart of 20W-50.

 

i have the same exact issue with mine, dealer told me it probably is the oil pressure sending unit, but my needle on the oil pressure bounces sometimes when idleing when fully warmed up. i got a LS6 oil pump just need to install it and that should help my oil pressure out alot also and gonna be changing to synthetic oil.

 

I get different pressures when i switch to different weights.

 

engine has 94k and i use mobil one 5w30 always have but i am glad to hear that this does not seem to be a prob... pressure does not drop at wot

 

My oil pressure (at least by stock gauge) has pretty much never been over 35 at idle when -fully- warmed up regardless of oil weight. ...and I've never ran an aftermarket gauge on mine to see just how accurate our OP sender/gauge is.

 

mine doesn't drop that low but close to it and i've heard from diff. people that there isn't much to worry about.

 

just my 2 cents

 

i would only worry about it if you have like 15psi or less. i've had numerous engines that only had like 20 psi when warm after i build them. plastigauged them all(every one i build) and all have been in limits and sometimes even on the tight side. but when you give it gas it jumps way up. it also depends on what rpm your car idles at. my M6 idles at like 800rpm and my friends A4 idles at like 500rpm. that will make a difference on oil pressure at idle.

 

yea that sound about wright, but like that other guy said check the ever so craptacular sending unit, it might be on its way out if anything.

 

Am glad to have found this thread. Just installed an aftermarket gauge & sender. Pressure @ cold idle was 25 p.s.i. & hot idle around 22-23 p.s.i.. Was 37p.s.i. cold & maybe 28 p.s.i. hot @ 3,000 RPM. Part of the low oil pressure may be due to the thin dino oil I'm using for an Autorx rinse phase. Anyway, from what I have read here sounds like everything is o.k..

 

GM DID in fact put a crapy oil P in our cars because they felt that even with the new firing order the needed lube film is thicker; higher oil P and higher oil VOLUME involved pumping losses thereby (spelling) HP loses.

I personaly would put a couple of SS washers (about .080"worth) between the alen cap and the spring in the oil pump before installing.
is it worth to loose a couple of hp instead of having 10-15psi more.... hmmmm I will sleep better......!

check my comments for pump installation on this thread
https://ls1tech.com/forums/generation-iii-internal-engine/412080-ls1-timing-chain-tension-question.html