Any real harm in running SAE 30 during summer?

[EMPIRE]

Originally Posted By: Al
I'll say it: All this is silly. A 10W-30 and a straight 30 wt. both have a viscosity of about 20 cSt. at around 170 F. So anything below 170 F the 10W-30 flows better and conversily the straight 30 does not lubricate as well on startup. At 80F the 30 weight is about twice as thick..200 cST. vs 110 cST. for the 10W-30. Even when a 10W-30 thins out to less than 8 cST we can't even see any wear problems in a normal car.

What am I missing here????


but conversely, i cant find any reports anywhere (scientific or just from motor tear down visuals) that indicate using a sae30 (in warm to hot climates) causes more damage than say its multigrade counterpart 10w30. as i mentioned, i was after a sae30 for its better cooling ability.

 

[jpr]

Originally Posted By: EMPIRE
i was after a sae30 for its better cooling ability.
I don't understand that statement.

 

[Al]

Originally Posted By: EMPIRE
i was after a sae30 for its better cooling ability.

I know of no reason why a 30 wt. should cool better.
And even if it did cool 1% better there is no evidence that better cooling in the bearing area is needed.

 

[Chris71]

I have Shell 30 wt. and a Pure One filter in my 4.7 Dakota right now. Usually run it every summer although I usually run Pennzoil.

 

[Chris71]

30 wt? [censored], We have straight 40 weight Brad Penn Penn Grade 1 in our 440 Dodge Coronet right now.

 

[EMPIRE]

Originally Posted By: Al
Originally Posted By: EMPIRE
i was after a sae30 for its better cooling ability.

I know of no reason why a 30 wt. should cool better.
And even if it did cool 1% better there is no evidence that better cooling in the bearing area is needed.

its not just in bearing areas where engine oil cools. the #2 function of motor oil is to cool. i know that the long chained polymer additives used to create multigrade oils changes the oil's cooling ability by appreciable amount. it is obvious that the multigrades work ok (meaning they function ok at hi temps, but they may not move heat like a straight grade oil), but if i can get better cooling by simply using a sae30 then why should i not get that better cooling ability, even if were just 1%?

 

[EMPIRE]

Originally Posted By: jpr
Originally Posted By: EMPIRE
i was after a sae30 for its better cooling ability.
I don't understand that statement.

the #2 function of engine oil is for cooling purposes. as i mentioned before, the long chained polymers use to make a oil multigrade dont move heat as well as a straight grade oil does.

 

[Al]

Originally Posted By: EMPIRE
i know that the long chained polymer additives used to create multigrade oils changes the oil's cooling ability by appreciable amount. it is obvious that the multigrades work ok (meaning they function ok at hi temps, but they may not move heat like a straight grade oil), but if i can get better cooling by simply using a sae30 then why should i not get that better cooling ability, even if were just 1%?


Let me see the source of your information. And tell me why you feel extra cooling is necessary. Besides a 10W-30 synthetic doesn't need polymers. You are arguing for the sake of arguing..which is fine. Just admit you want to use the 30 wt. for the [censored] of it. I can accept that.

 

[Dieselbob]

Correct me if I'm wrong, but isn't the extra cooler ability why 30 wt. is still specified in small air cooled engines?

 

[EMPIRE]

Originally Posted By: Al

Let me see the source of your information. And tell me why you feel extra cooling is necessary. Besides a 10W-30 synthetic doesn't need polymers. You are arguing for the sake of arguing..which is fine. Just admit you want to use the 30 wt. for the [censored] of it. I can accept that.


Al,
i dont know your background but from the sounds of it you dont know too much about engine oil, i may be wrong, but what you write makes me wonder.

here's just one of many many docs that say basically the same thing that i already know (http://www.amsoil.com/lit/g52.pdf). they say 40% of engine cooling is provided by the motor oil.

my background is in nuclear engineering. motor oil was not a minor of mine, but chemistry and materials was a core portion of my background.

i'm not arguing for sake of arguing. facts are the oil is responsiuble for a high % of engine cooling, and, the long chained polymer additives that make a base oil multigrade hurts cooling ability. i'll admit, as i already have, with todays available oil grades i dont know how much better a synth sae30 cools over a multigrade synth, but i do know the sae30 would cool better. so if it cools better and all else is equal/acceptable, then why not use the sae30 ??

 

[EMPIRE]

Originally Posted By: Dieselbob
Correct me if I'm wrong, but isn't the extra cooler ability why 30 wt. is still specified in small air cooled engines?

i dont think so. air cooled engines have larger tolerances, hence they can use straight grade oils over a wider temp range, etc.

 

[BuickGN]

What do you have against the Amsoil ACD? It has no VIIs and is a straight 30wt but can be called a 10-30 because it flows well when cold. I've put a gallon in the freezer and I was amazed at how well it flowed at freezing temps.

I run it year round in my Acura.

 

[jpr]

Originally Posted By: EMPIRE
Originally Posted By: Al

Let me see the source of your information. And tell me why you feel extra cooling is necessary. Besides a 10W-30 synthetic doesn't need polymers. You are arguing for the sake of arguing..which is fine. Just admit you want to use the 30 wt. for the [censored] of it. I can accept that.


Al,
i dont know your background but from the sounds of it you dont know too much about engine oil, i may be wrong, but what you write makes me wonder.

here's just one of many many docs that say basically the same thing that i already know (http://www.amsoil.com/lit/g52.pdf). they say 40% of engine cooling is provided by the motor oil.

my background is in nuclear engineering. motor oil was not a minor of mine, but chemistry and materials was a core portion of my background.

i'm not arguing for sake of arguing. facts are the oil is responsiuble for a high % of engine cooling, and, the long chained polymer additives that make a base oil multigrade hurts cooling ability. i'll admit, as i already have, with todays available oil grades i dont know how much better a synth sae30 cools over a multigrade synth, but i do know the sae30 would cool better. so if it cools better and all else is equal/acceptable, then why not use the sae30 ??

You seem to have missed the point of the question - nobody is questioning that engine oil provides a high % of engine cooling.

The question is to what extent do long chain polymer additives inhibit this function. The corollary questions are does it have in practical significance and if so, is it enough to make the increased low temp viscosity a reasonble trade off.

 

[Al]

Originally Posted By: jpr

You seem to have missed the point of the question - nobody is questioning that engine oil provides a high % of engine cooling.

The question is to what extent do long chain polymer additives inhibit this function. The corollary questions are does it have in practical significance and if so, is it enough to make the increased low temp viscosity a reasonble trade off.

Thank you

Empire: ..I never said I knew it all. I'm a mechanical Engineer and worked with equipment my whole working careey. Lubrication was one of my specialties. So I know a couple of things about oil. One thing I know is that the heat generated in a bearing is a function of load, speed, and viscosity. As far as carrying away the heat of course the oil does that. But in an automobile engine engine oil removes for the most part only heat generated in bearings. I would seriously doubt there is a difference in Heat capacity or thermal conductivity coefficient between the two oils.

I'm still looking for that link..the one you gave me didn't go anywhere. And I was hoping for something other than Amsoil Propaganda. (I have nothing against Amsoil)

 

[Drivebelt]

Quote:
Correct me if I'm wrong, but isn't the extra cooler ability why 30 wt. is still specified in small air cooled engines?


No. While one of the functions of oil is to cool parts of the engine, the difference in cooling ability between an oil with/without VII's should be small to negligible. Straight 30 wt is specified in small air-cooled engines because these engines run hot. VII's tend to break down in a hot environment which can lead to loss of viscosity protection. Generally, straight wt's don't have these VII's so they don't suffer loss of viscosity protection to the extent that a VII multigrade would in a very hot running engine by having the VII's shear (oxidize/break) down.

This is not as much an issue with modern HVI (high-viscosity-index) base oils like Group II/II+, or synthetics, (compared to the older Group I based oils like a 5W-30), and modern oils with better VII's -- but it still is a consideration.

 

[EMPIRE]

Originally Posted By: jpr

You seem to have missed the point of the question - nobody is questioning that engine oil provides a high % of engine cooling.

The question is to what extent do long chain polymer additives inhibit this function. The corollary questions are does it have in practical significance and if so, is it enough to make the increased low temp viscosity a reasonble trade off.


i'm not convinced i have traded anything using a sae30 synth (which typically exhibits 10w30 qualities as others have noted) in a hotter summer climate like Las Vegas, Phoenix, etc, over using a muligrade 10w30 synth. so since i traded nothing and we all seem to agree that a oil without the polymer multigrade additives will cool better (how much better TBD) then i still propose the "hence", sae30 synth would be a better choice.

as also mentioned, a straight oil will actually last longer than a multigrade because the additives in a multigrade break down over time and the upper end viscosity ratings get degraded.

 

[EMPIRE]

Originally Posted By: BuickGN
What do you have against the Amsoil ACD? It has no VIIs and is a straight 30wt but can be called a 10-30 because it flows well when cold. I've put a gallon in the freezer and I was amazed at how well it flowed at freezing temps.

I run it year round in my Acura.


hmm, not really sure i have anything against AMSoil, i am a AMSoil dealer. i need to look into some of their products more.

 

[jpr]

Originally Posted By: EMPIRE
Originally Posted By: jpr

You seem to have missed the point of the question - nobody is questioning that engine oil provides a high % of engine cooling.

The question is to what extent do long chain polymer additives inhibit this function. The corollary questions are does it have in practical significance and if so, is it enough to make the increased low temp viscosity a reasonble trade off.


i'm not convinced i have traded anything using a sae30 synth (which typically exhibits 10w30 qualities as others have noted) in a hotter summer climate like Las Vegas, Phoenix, etc, over using a muligrade 10w30 synth. so since i traded nothing and we all seem to agree that a oil without the polymer multigrade additives will cool better (how much better TBD) then i still propose the "hence", sae30 synth would be a better choice.

as also mentioned, a straight oil will actually last longer than a multigrade because the additives in a multigrade break down over time and the upper end viscosity ratings get degraded.

You need another "do over"...this time you missed actually answering my questions regarding differential cooling ability.

I do agree that from a viscosity standpoint, there doesn't appear to be relevant difference between a 10W-30 and synthetic SAE 30. But under what conditions would there be a practical benefit to running a synthetic SAE 30 instead of a synthetic 0W-30?

Also, there's more to oil than just viscosity. For example, the Redline SAE 30 you mentioned earlier is a "race oil" and Redline themselves recommends against using it as substitute for "street oil"

 

[EMPIRE]

Originally Posted By: jpr
You need another "do over"...this time you missed actually answering my questions regarding differential cooling ability.

I do agree that from a viscosity standpoint, there doesn't appear to be relevant difference between a 10W-30 and synthetic SAE 30. But under what conditions would there be a practical benefit to running a synthetic SAE 30 instead of a synthetic 0W-30?

Also, there's more to oil than just viscosity. For example, the Redline SAE 30 you mentioned earlier is a "race oil" and Redline themselves recommends against using it as substitute for "street oil"

i am only talking about synth oil, not a dino 10w30 vs. a sae30 synth.

if as others have said, if a sae30 synth exhibits 10w30 properties than is it safe to say a 10w30 synth exhibits 0w30 properties? if its labeled "10w30" or "0w30" i expect it to be in that specific range. if a sythn is rated "sae30" then it should act like sae30 and not like a 10w30, otherwise just call it "straight grade 10w30 synth", which would indicate to me that the oil is synth, acts like a 10w30, but has no multigrade VI's added (hey, AMSoil 10w30/sae30 ACD is just that), etc. thats kinda what i am looking for

i cannot dig up the links i have on heat capacity for motor oils. once we get that # for some various oils we can discuss the differences/benefits of each, etc. if anyone has links to such data please post.

i'm gonna take a closer look at AMSoil ACD 10w30/sae30.

 

[jpr]

So to summarize, you actually have no data supporting "better cooling ability" of an SAE 30 vs a comparable multigrade.