Oh Nooooo… another oil question
Thread Starter
Instructor
Joined: May 2019
Posts: 148
Likes: 35
From: Virginia
Oh Nooooo… another oil question
Not starting another which oil is best thread please….looking for real world “I have done this” comments please…
In attempting to reduce the different types of oils on my garage shelf I’m curious if anyone has ran M1 0-40 in their C5…. Currently using M1 10-30 in my 01 base with no issues but I run the 0-40 in our 3 BMWs with no issues either. So I could keep the same weight synth oil for all those cars by switching over the C5.
I live in Virginia so it’s a moderately mild climate and it’s mainly a fair weather weekend car.
I don’t believe I will see much difference between the two weights but I was curious if anyone had ran the 0-40 for any length of time….. thanks
In attempting to reduce the different types of oils on my garage shelf I’m curious if anyone has ran M1 0-40 in their C5…. Currently using M1 10-30 in my 01 base with no issues but I run the 0-40 in our 3 BMWs with no issues either. So I could keep the same weight synth oil for all those cars by switching over the C5.
I live in Virginia so it’s a moderately mild climate and it’s mainly a fair weather weekend car.
I don’t believe I will see much difference between the two weights but I was curious if anyone had ran the 0-40 for any length of time….. thanks
Le Mans Master
Joined: Oct 2007
Posts: 9,700
Likes: 3,469
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
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St. Jude Donor '09-'10-'11
I run 10-W40 on my track driven street car without issue. Just know that on cold days (like below 40°F) the oil will take longer to get everywhere. I let it sit and idle for a min before trying to move. You should be good in your climate though.
Race Director
Joined: Oct 2004
Posts: 12,864
Likes: 4,668
Not starting another which oil is best thread please….looking for real world “I have done this” comments please…
In attempting to reduce the different types of oils on my garage shelf I’m curious if anyone has ran M1 0-40 in their C5…. Currently using M1 10-30 in my 01 base with no issues but I run the 0-40 in our 3 BMWs with no issues either. So I could keep the same weight synth oil for all those cars by switching over the C5.
I live in Virginia so it’s a moderately mild climate and it’s mainly a fair weather weekend car.
I don’t believe I will see much difference between the two weights but I was curious if anyone had ran the 0-40 for any length of time….. thanks
In attempting to reduce the different types of oils on my garage shelf I’m curious if anyone has ran M1 0-40 in their C5…. Currently using M1 10-30 in my 01 base with no issues but I run the 0-40 in our 3 BMWs with no issues either. So I could keep the same weight synth oil for all those cars by switching over the C5.
I live in Virginia so it’s a moderately mild climate and it’s mainly a fair weather weekend car.
I don’t believe I will see much difference between the two weights but I was curious if anyone had ran the 0-40 for any length of time….. thanks
Le Mans Master
Joined: Feb 2021
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From: Florida
2025 Corvette of the Year Finalist - Unmodified
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Just a thought…some of the foreign brands are really picky about their oil. My wife’s Audi doesn’t even have a dipstick, so you have to add a few ounces at a time, wait a couple of minutes, then turn on the key so the computer will tell you if the level is within spec!
In addition, the owners manual calls for a very specific composition that my other oil did not contain. As I recall it had something to do with a minimum grade VW specification. So, you may be OK on weight, but I would check out both factors.
I found both items covered in the owners manual.
In addition, the owners manual calls for a very specific composition that my other oil did not contain. As I recall it had something to do with a minimum grade VW specification. So, you may be OK on weight, but I would check out both factors.
I found both items covered in the owners manual.
Melting Slicks
Joined: Jun 2001
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Drifting
Joined: Nov 2005
Posts: 1,320
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From: NW Chicago
St. Jude Donor '12-'13-'14-'15
I have liquid/liquid oil cooler & aftermarket radiator. Oil temp 190-200 daily driving, 200-218 autocross/ road track, same oil pressure as 5-30. I believe the 0-40 has higher zinc and phosphorous, like the old M1 when my car was built in 99. I figured quicker lubrication when cold and thicker when hot.
Le Mans Master
Joined: Sep 2006
Posts: 6,050
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From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
Oil
Oil weight is the first number 0.
They add a thickening agent that reacts with heat. The hotter it gets, the thicker it gets to the rated thickness.
over time, this thickener loses it’s effectiveness, and ghe oil gets thinner. The reason the oil turns black is the contaminants in the oil, which adds viscosity to a point.
just gollow mfg’s oil change recommendations to prevent thinnrr oil and sludge deposits.
fo a simple test.
just before hour next oil change, write or make a note on your phone, your oil pressure.
then change the oil snd gilter, and note hour new oil pressure. They dhould be different.
In Phoenix, after months of 117 degree days,
i can pick up 10 psi with an oil change.
They add a thickening agent that reacts with heat. The hotter it gets, the thicker it gets to the rated thickness.
over time, this thickener loses it’s effectiveness, and ghe oil gets thinner. The reason the oil turns black is the contaminants in the oil, which adds viscosity to a point.
just gollow mfg’s oil change recommendations to prevent thinnrr oil and sludge deposits.
fo a simple test.
just before hour next oil change, write or make a note on your phone, your oil pressure.
then change the oil snd gilter, and note hour new oil pressure. They dhould be different.
In Phoenix, after months of 117 degree days,
i can pick up 10 psi with an oil change.
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Team Owner
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From: Virginia
St. Jude Donor '11
Le Mans Master
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From: Florida
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I was referring to you trying to use the same oil for both cars, including the BMW. The C5 is easy, Mobil 1 5W-30. It’s the BMW that may have specific ingredients or standard.
The BMW oil of the same weight may be fine for the Vette, but not necessarily the other way around. The owners manual for each car should have all the specs in addition to the viscosity.
The BMW oil of the same weight may be fine for the Vette, but not necessarily the other way around. The owners manual for each car should have all the specs in addition to the viscosity.
Le Mans Master
Joined: Oct 2007
Posts: 9,700
Likes: 3,469
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
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St. Jude Donor '09-'10-'11
Oil weight is the first number 0.
They add a thickening agent that reacts with heat. The hotter it gets, the thicker it gets to the rated thickness.
over time, this thickener loses it’s effectiveness, and ghe oil gets thinner. The reason the oil turns black is the contaminants in the oil, which adds viscosity to a point.
just gollow mfg’s oil change recommendations to prevent thinnrr oil and sludge deposits.
fo a simple test.
just before hour next oil change, write or make a note on your phone, your oil pressure.
then change the oil snd gilter, and note hour new oil pressure. They dhould be different.
In Phoenix, after months of 117 degree days,
i can pick up 10 psi with an oil change.
They add a thickening agent that reacts with heat. The hotter it gets, the thicker it gets to the rated thickness.
over time, this thickener loses it’s effectiveness, and ghe oil gets thinner. The reason the oil turns black is the contaminants in the oil, which adds viscosity to a point.
just gollow mfg’s oil change recommendations to prevent thinnrr oil and sludge deposits.
fo a simple test.
just before hour next oil change, write or make a note on your phone, your oil pressure.
then change the oil snd gilter, and note hour new oil pressure. They dhould be different.
In Phoenix, after months of 117 degree days,
i can pick up 10 psi with an oil change.
Le Mans Master
Joined: Oct 2007
Posts: 9,700
Likes: 3,469
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
I was referring to you trying to use the same oil for both cars, including the BMW. The C5 is easy, Mobil 1 5W-30. It’s the BMW that may have specific ingredients or standard.
The BMW oil of the same weight may be fine for the Vette, but not necessarily the other way around. The owners manual for each car should have all the specs in addition to the viscosity.
The BMW oil of the same weight may be fine for the Vette, but not necessarily the other way around. The owners manual for each car should have all the specs in addition to the viscosity.
Race Director
Joined: Oct 2004
Posts: 12,864
Likes: 4,668
Oil weight is the first number 0.
They add a thickening agent that reacts with heat. The hotter it gets, the thicker it gets to the rated thickness.
over time, this thickener loses it’s effectiveness, and ghe oil gets thinner. The reason the oil turns black is the contaminants in the oil, which adds viscosity to a point.
just gollow mfg’s oil change recommendations to prevent thinnrr oil and sludge deposits.
fo a simple test.
just before hour next oil change, write or make a note on your phone, your oil pressure.
then change the oil snd gilter, and note hour new oil pressure. They dhould be different.
In Phoenix, after months of 117 degree days,
i can pick up 10 psi with an oil change.
They add a thickening agent that reacts with heat. The hotter it gets, the thicker it gets to the rated thickness.
over time, this thickener loses it’s effectiveness, and ghe oil gets thinner. The reason the oil turns black is the contaminants in the oil, which adds viscosity to a point.
just gollow mfg’s oil change recommendations to prevent thinnrr oil and sludge deposits.
fo a simple test.
just before hour next oil change, write or make a note on your phone, your oil pressure.
then change the oil snd gilter, and note hour new oil pressure. They dhould be different.
In Phoenix, after months of 117 degree days,
i can pick up 10 psi with an oil change.
Le Mans Master
Joined: Jul 2010
Posts: 6,013
Likes: 726
Not to start trouble, but I believe there is no oil that thickens as it warms. AFAIK, ALL oils thin out as they warm. If oil thickened as it was heated, everyone would change their oil when the engine, and oil, are cold, not hot!! I'm 99% certain that the additives help control the rate at which the oil thins as heat is introduced. My .02
Motor oil gets thinner as it's heated, but to prevent it from getting too thin at higher temperatures, additives (viscosity modifiers) are used so that it behaves like a thicker grade oil at higher temps. ... The lower the first number, the better the oil will pump and flow at cold startups.
Le Mans Master
Joined: Feb 2021
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From: Florida
2025 Corvette of the Year Finalist - Unmodified
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I found an article that explains how viscosity is altered. Just for fun…
” In the mid-1950s, oil industry chemists developed an oil additive called a Viscosity Index Improver (VII). Viscosity Index (VI) is a description of the rate at which oil will change viscosity as temperature changes, all oils thicken in viscosity as temperature drops and thin in viscosity as temperature rises, good quality virgin mineral oil has a VI of around 95 to 100. The newly developed Viscosity Index Improver (VII) additive changed the rate at which oil thickened as temperature dropped and thinned as temperature rose. An oil modified with a Viscosity Index Improver still thickens as temperature drops, but it doesn’t thicken as much as a non-modified oil. Nor does it thin out as much as the temperature rises.
A Viscosity Index Improver (VII) additive is an organic chain molecule which is bundled up like a ball of spaghetti and dissolves in the oil. When cold the VII molecule shrinks and the oil has less resistance flowing passed – less resistance to flow, lower viscosity oil. When hot, the VII molecule swells and produces higher resistance to the oil flowing passed, the oil has still thinned out due to the temperature rise but now it has a higher viscosity than if the VII was not there.“
” In the mid-1950s, oil industry chemists developed an oil additive called a Viscosity Index Improver (VII). Viscosity Index (VI) is a description of the rate at which oil will change viscosity as temperature changes, all oils thicken in viscosity as temperature drops and thin in viscosity as temperature rises, good quality virgin mineral oil has a VI of around 95 to 100. The newly developed Viscosity Index Improver (VII) additive changed the rate at which oil thickened as temperature dropped and thinned as temperature rose. An oil modified with a Viscosity Index Improver still thickens as temperature drops, but it doesn’t thicken as much as a non-modified oil. Nor does it thin out as much as the temperature rises.
A Viscosity Index Improver (VII) additive is an organic chain molecule which is bundled up like a ball of spaghetti and dissolves in the oil. When cold the VII molecule shrinks and the oil has less resistance flowing passed – less resistance to flow, lower viscosity oil. When hot, the VII molecule swells and produces higher resistance to the oil flowing passed, the oil has still thinned out due to the temperature rise but now it has a higher viscosity than if the VII was not there.“
Safety Car
Joined: Dec 2011
Posts: 4,704
Likes: 239
From: Redondo Beach CA
Check on a bottle and see if mobil 1 still has a 1-800 oil advice phone line. I got some good information when I called, and the more information, or more correctly, factual information, since this is an internet oil discussion, the better the decision.
They even gave me advice about oil for my record player, after checking with the lab, saying that a zero viscosity would offer no benefits over the 5- 30 I run in the main bearing, until zero degrees.
When I asked about fuel saving oil, I learned what should have been obvious to me, that modern valve trains are designed for ultra fuel efficiency and need a very different and specific oil than the other stuff on the shelf. So I suppose the old crap about not mixing oil has finally come true.
They even gave me advice about oil for my record player, after checking with the lab, saying that a zero viscosity would offer no benefits over the 5- 30 I run in the main bearing, until zero degrees.
When I asked about fuel saving oil, I learned what should have been obvious to me, that modern valve trains are designed for ultra fuel efficiency and need a very different and specific oil than the other stuff on the shelf. So I suppose the old crap about not mixing oil has finally come true.