5.7 TBI Low Oil Pressure Solution.

[shelbyt.67]

Hey all. Seen several questions about oil pressure dropping to oh $hit level at idle when hot. Mines been doing that fer 8 months. Pressure is high until engine gets to operation temp (190), then levels off to 10 PSI per 1000 rpm at running speed. Then drops to zilch at the stop light with the check gauges light blinking at me.
Guess what?
Right about 8 months ago I changed my oil filter to a high filtration Mobil 1. Today I installed a remote oil filter that required a standard base Fram filter. Drivin to town I noticed my oil pressure never dropped below 6 PSI at idle. No oh $hit and no blinkin light.
I'm guessing the boys at the factory never expected the 5.7 TBI engine to have anything more than a standard paper oil filter. Hope this helps.

 

[SkyHighColorado]

Hey all. Seen several questions about oil pressure dropping to oh $hit level at idle when hot. Mines been doing that fer 8 months. Pressure is high until engine gets to operation temp (190), then levels off to 10 PSI per 1000 rpm at running speed. Then drops to zilch at the stop light with the check gauges light blinking at me.
Guess what?
Right about 8 months ago I changed my oil filter to a high filtration Mobil 1. Today I installed a remote oil filter that required a standard base Fram filter. Drivin to town I noticed my oil pressure never dropped below 6 PSI at idle. No oh $hit and no blinkin light.
I'm guessing the boys at the factory never expected the 5.7 TBI engine to have anything more than a standard paper oil filter. Hope this helps.

I think that has more to do with you changing the oil. I would try running 10w30 and some Lucas oil stabilizer to increase pressure.

 

[GMstrong]

Try replacing the oil pressure switch,or the oil pump.If the motor has high mileage probably just tired.I would never run lucas oil stabilizer its starts breaking down and foaming due to high heat.If you run lucas,get your motor up to operating temp and pull you dipstick youll see foam on it depending on how much you use.

 

[great white]

If you're seeing below 5 at idle, sorry to say but you're hooped if it's not a bad oil pressure sender.

Changing filter "types" shouldn't make a bit enough difference unless the filter had a failure of the bypass valve.

6 PSI is also not good. Your engine is very near the end of it's useful life.

Your rod or main bearings are opening up, or possibly your oil pump is worn. Most likely it's all of it, as engines wear as an assembly and the everything in the oil system sees the same pressure, wear and contaminants.

Once you start seeing under 5 psi, it's only a matter of time until you spin a bearing or some other pressure related failure.

As a minimum, I'd start looking at "thicker" grade oils if you want it to live a bit longer.

I've run really bad engines on straight 50W before to just nurse 'em out a bit more. Winter starting was an experience with those weights.....

Most oil pressure is measured at a specific RPM for an engine type. Same as idle speed oil pressure recommendations. Believe it or not, these are usually listed in the owners manual. Pull yours out and have a look.

Don't start throwing "snake oil in a bottle" products into the engine. Those are designed to do one thing and one thing only: Lighten your wallet....

 

[shelbyt.67]

Thx fer the input guys. This post is aimed at those folks who have asked about the check light blinkin suddenly out of the blue. I know my motor is worn but the sticker here is the sudden drop of pressure from normal pressure as opposed to a slow reduction over time. I've changed the sending unit twice and now I'm runnin a mech gauge and 10w40. My sudden drop of pressure occurred right about the same time I put the Mobil 1 on. So with the increase in pressure after installin the base fram filter, I figured the filter was the reason for the sudden drop.

 

[jdyates]

If you're seeing below 5 at idle, sorry to say but you're hooped if it's not a bad oil pressure sender.

Changing filter "types" shouldn't make a bit enough difference unless the filter had a failure of the bypass valve.

6 PSI is also not good. Your engine is very near the end of it's useful life.

Your rod or main bearings are opening up, or possibly your oil pump is worn. Most likely it's all of it, as engines wear as an assembly and the everything in the oil system sees the same pressure, wear and contaminants.

Once you start seeing under 5 psi, it's only a matter of time until you spin a bearing or some other pressure related failure.

As a minimum, I'd start looking at "thicker" grade oils if you want it to live a bit longer.

I've run really bad engines on straight 50W before to just nurse 'em out a bit more. Winter starting was an experience with those weights.....

Most oil pressure is measured at a specific RPM for an engine type. Same as idle speed oil pressure recommendations. Believe it or not, these are usually listed in the owners manual. Pull yours out and have a look.

Don't start throwing "snake oil in a bottle" products into the engine. Those are designed to do one thing and one thing only: Lighten your wallet....

I have a repair manual that has a whole page for specific engine codes and what the pressure should be at certain RPMs. Ill snap a pic and post it later if I remember. I think a 5.7 should be 18psi at 2000rpm or something.

 

[shelbyt.67]

^^^ Yes, The 5.7 TBI runs at a lower oil psi than the Vortec. Roughly 10+ psi per 1000 rpm is normal. With the Mobil 1 filter I was runnin 6-8 psi per 1000 rpm. Now with the basic Fram filter I'm runnin 14 psi at 1000 rpm. At 600 rpm idle I was at about 2-3 psi. Now I'm at 8-10 psi. The only thing that I changed was installing the remote filter setup with a basic filter.

 

[TylerZ281500]

did u put a mechacal test guage to check oil pressure?

 

[shelbyt.67]

did u put a mechacal test guage to check oil pressure?

No. I'm goin off of the mechanical Autometer in the truck.

 

[jdyates]

What's a remote filter setup?