Oil pressure! I need straight answers!

**1998 T/A** · 07-15-2014, 06:16 PM

Ok, it's 10am and I fire the car up. Oil pressure sits a few psi above 40, 45 if I had to guess. Cruising on the highway just a few psi under 40, 36-38. City driving I'd put it at 31 conservatively and hot idle at a stop light it dips down to maybe 24-28. I know this has been debated back and forth but do I have reason to be alarmed? Hard acceleration it goes up as it should, nothing that concerns me there. The gauge itself is a little jumpy but I'm not sure if that's normal. Thanks fellas.

**pajeff02** · 07-15-2014, 06:29 PM

The old rule of thumb is at least 10 psi of oil pressure for every 1,000 rpm. How many miles on the engine and what weight oil are you running? Personally, I think your oil pressure is fine assuming your gauge is accurate.

**Too Fast** · 07-16-2014, 02:42 AM

^^^I agree with Jeff. If the gauge is jumpy, it could be a failing OPSU. On GMs, they tend to fail reading higher then normal, not lower.

**1998 T/A** · 07-16-2014, 02:14 PM

I'm running 5 dub ya 30 Mobil 1 on her and she has 11th on the clock. I threw some engine restorer in the last oil change and it bumped it a few psi nothing significant. I think I am fine just wanted input from some knowledgeable people

- - - Updated - - -

114k on 11th

**Too Fast** · 07-18-2014, 02:54 PM

The engine restorer is probably very thick viscosity, compared to our engine's call for 5 dub ya 30. That's prolly what raised the pressure a few psi.

**1998 T/A** · 07-18-2014, 04:25 PM

Ya it was thicker than regular oil...I may sea foam but heard some horror stories, any of you guys use it pros? Cons?

**pajeff02** · 07-19-2014, 03:54 AM

I wouldn't dump that stuff in my engine. Penzoil Platinum would be the recommended oil if you are concerned about sludge or other buildup in the crankcase.

**Falco78** · 08-04-2014, 08:13 PM

Mobile 1 0w40 raised my hot running oil pressure from about 38 to 47

**jb3golf** · 08-05-2014, 08:59 PM

Couple of questions here: Did you recently perform any oil changes/cam changes and/or any internal work? Also if I were you i would put in valvoline conventional 20w50 oil...i guarantee your pressure will Improve and stabilize....this viscosity and brand is what an LSX engine builder told me to do with no compromises...it has worked to perfection. ..just my .02...

**pajeff02** · 08-06-2014, 02:33 AM

I would only consider 20W-50 in much warmer climates... and even then I would probably not run it. These engines are designed to run with 5W-30 in the oil pan. Granted, if you open up your bearing clearances on purpose, then you probably want to head in that direction. Otherwise, stick with the recommended oil, or close to it.

**Too Fast** · 08-06-2014, 02:39 AM

Yep. And thicker oil does cost HP, been proven just a couple times.

**pajeff02** · 08-06-2014, 02:54 AM

Most engine wear occurs on cold startup too. Best to have that oil flowing as fast as it can to the main and cam bearing journals.

**Firebirdjones** · 08-06-2014, 04:53 AM

Some interesting facts I've found while reading and experimenting with oils. I've found some of your more expensive 20W oils actually flow better cold than alot of the "off the shelf" brand 5W and 10W oils.
I've been paying attention to the "poor" tests done which is specifically for cold flow values. Your Amsoil 20W's and a couple other high end brands like Brad Penn actually have better cold flow characteristics than off shelf 5 and 10W oils like Valvoline and the like.
I'm no oil expert but I believe that's directly related to the oil additive packages and how they work, and the more expensive oils just have a better additive package. If I can figure out how to link a "poor" value chart I'll post it here.
I've since switched all cars over to Amsoil. I run their high zinc oils in everything including the LS engines. I run the 20W-50 in all the older stuff, and run 10W-40 in the LS and the little 89 5.0.

**Firebirdjones** · 08-06-2014, 07:50 AM

Here you go, interesting info. The pour values are interesting here. Pour values are where the oil is still capable of flowing at that temp. Which is directly related to cold start flow characteristics. This would be strictly the first number in multi-viscosity oils. If you compare the 20W Amsoil at the top of the chart to other brand X oils you can see the pour value is actually a lower temp than most others, even those with a lower viscosity rating. At -47 degrees Amsoil still flows better than nearly every 10w oil listed and better than half of the 5w oils listed. Even dropping down to a 10w Amsoil the pour temp is only increased to -54 degrees, a 7 degrees difference.

I find that pretty interesting. I'm pretty comfortable with the 20W Amsoil if it pours down to -47 degrees. Not many places in the country that get that cold, and if they did I sure as hell wouldn't be living there

Granted I don't believe I need that 20w viscosity in a stock LS engine, but I do run the 10w-40, even though the cold temp performance is nearly identical. I like the 40 weight for the hotter summer time temps we see here in the desert, yet I know it can still handle the colder temps if need be (even though we don't even come close to that pour temp rating around here

) Now when the time comes for a hotter LQ stroker build I might consider the 20w-50 at that point. But in a stockish LS1 right now I don't see the need.

Much Higher Viscosity Indexes and Flash Points: AMSOIL Synthetic Oils

**jb3golf** · 08-06-2014, 01:34 PM

Originally Posted by Firebirdjones

Here you go, interesting info. The pour values are interesting here. Pour values are where the oil is still capable of flowing at that temp. Which is directly related to cold start flow characteristics. This would be strictly the first number in multi-viscosity oils. If you compare the 20W Amsoil at the top of the chart to other brand X oils you can see the pour value is actually a lower temp than most others, even those with a lower viscosity rating. At -47 degrees Amsoil still flows better than nearly every 10w oil listed and better than half of the 5w oils listed. Even dropping down to a 10w Amsoil the pour temp is only increased to -54 degrees, a 7 degrees difference.

I find that pretty interesting. I'm pretty comfortable with the 20W Amsoil if it pours down to -47 degrees. Not many places in the country that get that cold, and if they did I sure as hell wouldn't be living there

Granted I don't believe I need that 20w viscosity in a stock LS engine, but I do run the 10w-40, even though the cold temp performance is nearly identical. I like the 40 weight for the hotter summer time temps we see here in the desert, yet I know it can still handle the colder temps if need be (even though we don't even come close to that pour temp rating around here

) Now when the time comes for a hotter LQ stroker build I might consider the 20w-50 at that point. But in a stockish LS1 right now I don't see the need.

I see your points here...very interesting. I do know that for my forged block the 20w50 is what I was instructed to use, but the bearing tolerances may account for the thicker viscosity. ..However the builder stated that LS1 ENGINES even in Stoc form could benefit.....thanks for the insight everone....I'm still wondering if something else is causing his oil pressure issue...
Much Higher Viscosity Indexes and Flash Points: AMSOIL Synthetic Oils

**Marc Brown** · 08-22-2014, 05:51 PM

I have 2002 camera n when i am at high rpm my oil pressure is dropping very low..i just did full oil change 5w30 full synthetic and found needle bearings in pan..what u think problem is rocker or cam bearings?

**pajeff02** · 08-23-2014, 04:48 AM

Needle bearings have to be coming from a rocker arm. Time to pull the rocker covers and check things out. You will want to count the needles once you have everything apart - hopefully you can find them all.