? on normal oil pressure??
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Intermediate
Joined: Sep 2013
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? on normal oil pressure??
Hello: My question is: what is considered normal oil pressure. At idle it shows 17, at 35 mph it shows 35 and at highway speeds it shows 41 to 42. Oil temp. is 202 at highway speeds. I have a 1989 corvette convertible with the LS98 350 engine. It is totally OEM and has 57,000 mile on it. I use Mobil 1 oil. Thank you in advance. It this was posted previously, I would be appreciative in knowing the link.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
Yessir....
That's pretty normal. It depends a LOT on the conditions, the oil wt or viscosity and the engine wear.
I did a very thorough write up on the mysteries of oil pressure a yr or two ago...I detailed the oil pressure and why it is what it is and what makes a difference. To make a long story short, when you start to see LOW pressures, jumping to a heavier wt oil is not always the solution. This is because the gauge you see is telling you how HARD it is for the pump to push the oil.....not necessarily how much oil is going thru the system. Because the sensor is near the top of the system, we can safely assume that the flow of oil is sufficient everywhere in between.
This is MY personal oil/pressure philosophy,
any oil is good oil, as long as its fresh or clean. As long as the pressure stays a minimum of 10 psi/ 1000 rpm you are in the safe range when its hot. It should be quite a bit more when its cold. Cold oil needs to be HOT,. hot oil is why your engine last as long as it does. Synthetics provide an extra margin of safety and longevity. I go 5000 on the synthetics where the conventional got changed at 2500. The annual cost is comparable on a spread sheet...actually, the synthetics edge out as cheaper over time.
Your pressure should be seen as a wear gauge of the engines internal health. Well maintained engines will show your current pressures at 200,000 miles IF they have been taken care of.
remember, when it was NEW, the oil pump showed you a higher pressure across the temp range.....because it was struggling to force oil thru tight bearings and wear surfaces.....again, pressure on the gauge is indicating how hard the pump is working/pushing on the fluid. The pressure numbers you see are whats left-over after the loss in bearings, the filter by-pass valve and other places for oil to weep out of the circuit.
The single biggest tell tale sign of an internal wear problem is the loss of pressure at idle when hot when/if there WAS pressure cold.... as long as that's not happening, you're golden.
That's pretty normal. It depends a LOT on the conditions, the oil wt or viscosity and the engine wear.
I did a very thorough write up on the mysteries of oil pressure a yr or two ago...I detailed the oil pressure and why it is what it is and what makes a difference. To make a long story short, when you start to see LOW pressures, jumping to a heavier wt oil is not always the solution. This is because the gauge you see is telling you how HARD it is for the pump to push the oil.....not necessarily how much oil is going thru the system. Because the sensor is near the top of the system, we can safely assume that the flow of oil is sufficient everywhere in between.
This is MY personal oil/pressure philosophy,
any oil is good oil, as long as its fresh or clean. As long as the pressure stays a minimum of 10 psi/ 1000 rpm you are in the safe range when its hot. It should be quite a bit more when its cold. Cold oil needs to be HOT,. hot oil is why your engine last as long as it does. Synthetics provide an extra margin of safety and longevity. I go 5000 on the synthetics where the conventional got changed at 2500. The annual cost is comparable on a spread sheet...actually, the synthetics edge out as cheaper over time.
Your pressure should be seen as a wear gauge of the engines internal health. Well maintained engines will show your current pressures at 200,000 miles IF they have been taken care of.
remember, when it was NEW, the oil pump showed you a higher pressure across the temp range.....because it was struggling to force oil thru tight bearings and wear surfaces.....again, pressure on the gauge is indicating how hard the pump is working/pushing on the fluid. The pressure numbers you see are whats left-over after the loss in bearings, the filter by-pass valve and other places for oil to weep out of the circuit.
The single biggest tell tale sign of an internal wear problem is the loss of pressure at idle when hot when/if there WAS pressure cold.... as long as that's not happening, you're golden.
Racer
Joined: Aug 2013
Posts: 250
Likes: 1
Yessir....
That's pretty normal. It depends a LOT on the conditions, the oil wt or viscosity and the engine wear.
I did a very thorough write up on the mysteries of oil pressure a yr or two ago...I detailed the oil pressure and why it is what it is and what makes a difference. To make a long story short, when you start to see LOW pressures, jumping to a heavier wt oil is not always the solution. This is because the gauge you see is telling you how HARD it is for the pump to push the oil.....not necessarily how much oil is going thru the system. Because the sensor is near the top of the system, we can safely assume that the flow of oil is sufficient everywhere in between.
This is MY personal oil/pressure philosophy,
any oil is good oil, as long as its fresh or clean. As long as the pressure stays a minimum of 10 psi/ 1000 rpm you are in the safe range when its hot. It should be quite a bit more when its cold. Cold oil needs to be HOT,. hot oil is why your engine last as long as it does. Synthetics provide an extra margin of safety and longevity. I go 5000 on the synthetics where the conventional got changed at 2500. The annual cost is comparable on a spread sheet...actually, the synthetics edge out as cheaper over time.
Your pressure should be seen as a wear gauge of the engines internal health. Well maintained engines will show your current pressures at 200,000 miles IF they have been taken care of.
remember, when it was NEW, the oil pump showed you a higher pressure across the temp range.....because it was struggling to force oil thru tight bearings and wear surfaces.....again, pressure on the gauge is indicating how hard the pump is working/pushing on the fluid. The pressure numbers you see are whats left-over after the loss in bearings, the filter by-pass valve and other places for oil to weep out of the circuit.
The single biggest tell tale sign of an internal wear problem is the loss of pressure at idle when hot when/if there WAS pressure cold.... as long as that's not happening, you're golden.
That's pretty normal. It depends a LOT on the conditions, the oil wt or viscosity and the engine wear.
I did a very thorough write up on the mysteries of oil pressure a yr or two ago...I detailed the oil pressure and why it is what it is and what makes a difference. To make a long story short, when you start to see LOW pressures, jumping to a heavier wt oil is not always the solution. This is because the gauge you see is telling you how HARD it is for the pump to push the oil.....not necessarily how much oil is going thru the system. Because the sensor is near the top of the system, we can safely assume that the flow of oil is sufficient everywhere in between.
This is MY personal oil/pressure philosophy,
any oil is good oil, as long as its fresh or clean. As long as the pressure stays a minimum of 10 psi/ 1000 rpm you are in the safe range when its hot. It should be quite a bit more when its cold. Cold oil needs to be HOT,. hot oil is why your engine last as long as it does. Synthetics provide an extra margin of safety and longevity. I go 5000 on the synthetics where the conventional got changed at 2500. The annual cost is comparable on a spread sheet...actually, the synthetics edge out as cheaper over time.
Your pressure should be seen as a wear gauge of the engines internal health. Well maintained engines will show your current pressures at 200,000 miles IF they have been taken care of.
remember, when it was NEW, the oil pump showed you a higher pressure across the temp range.....because it was struggling to force oil thru tight bearings and wear surfaces.....again, pressure on the gauge is indicating how hard the pump is working/pushing on the fluid. The pressure numbers you see are whats left-over after the loss in bearings, the filter by-pass valve and other places for oil to weep out of the circuit.
The single biggest tell tale sign of an internal wear problem is the loss of pressure at idle when hot when/if there WAS pressure cold.... as long as that's not happening, you're golden.
Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
To explain Lee's statement, if your main and rod bearings are worn out, low pressure will be seen especially when the vehicle is hot. Most cars will show a little more pressure cold and as everything heats up and expands the tolerances in the bearings increases (decreases?) causing less restriction hence lower pressure.
Thread Starter
Intermediate
Joined: Sep 2013
Posts: 43
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Thank you to everyone who replied to my question. I am in awe of the knowledge that is on this group to help all of us corvette owners. Thank you again and I will be back with another question the first of this week. Happy rides!
