Rethink and understand SAE viscosity: a 0W-20 can be thicker than a 0W-40 or 5W-40

OVERKILL

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“They said” … base oil composed of various base stocks can have a naturally good VI …
Yep, that's why I never understood the obsession with stratospherically high VI oils like TGMO, which you know is obtained using an obscene amount of VII and extremely light base oils. The Mobil 0W-20's had pretty middle-of-the-road VI's, pointing to low a VII content of around 4% for EP going by Gokhan's calculations, vs ~10% for TGMO. That's a huge difference.

That's roughly the same VII content as he estimates (4%) for Redline 10W-30 BTW.

My 0W-20 calculates as having 3.92% VII.
 
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Yep, that's why I never understood the obsession with stratospherically high VI oils like TGMO, which you know is obtained using an obscene amount of VII and extremely light base oils. The Mobil 0W-20's had pretty middle-of-the-road VI's, pointing to low a VII content of around 4% for EP going by Gokhan's calculations, vs ~10% for TGMO. That's a huge difference.

That's roughly the same VII content as he estimates (4%) for Redline 10W-30 BTW.

My 0W-20 calculates as having 3.92% VII.
I agree with that.

The better oils use less VIIs...
 

Foxtrot08

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Yep, and if my memory serves me correctly, didn't the pao thing begin when P66 bought out Redline?

P66 has changed 0 of the original redline formulations.

P66 only has added the API/ILSAC redline products to the redline line up .

They’ve also taken a number of redline formulations and used them in specialty oem applications.

P66 is very, very hands off management of redline. Actually took them 6 months to realize they had purchased them.
 
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Correct.

There CAN'T be a 100% Group V/ester because Group V is polarizing or something to do with stability of.. if I'm recalling correctly. Has to be off-set by something. Am I on the right track here?
Yeah,
Esters not carefully blended will screw up surface active AW, EP and DDI packages. Every polar molecule is competing for the metal surface. I think I remember, if I do correctly, that esters exceeding 20% or something close to that figure, is going to compromise wear protection and damage elastomers.
 
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Yeah,
Esters not carefully blended will screw up surface active AW, EP and DDI packages. Every polar molecule is competing for the metal surface. I think I remember, if I do correctly, that esters exceeding 20% or something close to that figure, is going to compromise wear protection and damage elastomers.
Sounds about right.

I have to pull in @High Performance Lubricants Dave into the discussion, if he is willing to participate. I am in LOVE with his brews containing ANs - Oh, Group V again.

PAO (Group V) plus POE (Need to have a whiteboard of some sort to take notes) is a great blend. Here is from about 9 and a half years ago (first searches led to POE in refrigerants. That's not what we are talking about here.) https://bobistheoilguy.com/forums/threads/do-majority-poe-base-oils-reduce-start-up-wear.199380/

Says POE and Group 3 base stocks are polar and PAO is not.. truth to that?
 

ZeeOSix

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Some more graphing of the data in the Excel spreadsheet in post #1.

1666991841435.jpeg


1666991860760.jpeg
 
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Sorry, that's crap.
.
Why do you say that? Companies and corporations are run by humans with all their frailties and vices contained therein. I should know. Directly or indirectly as a USAF enlisted technician, a consultant, an engineering contractor, or manager, I've worked for 4 different civilian companies and corps, 4 different federal government departments, and 5 different state and local governments. I've seen my share of good and bad, with a great many inherent human frailties exposed at some point. Much like the oil business, the telecom business is fluid. Come to think of it, some of my years were even spent on Alaska's North Slope working as an ARCO Alaska and Alyeska Pipeline Service Company contractor. Huh.

Nothing here surprises me, including attitudes.
 
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OVERKILL

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Yeah,
Esters not carefully blended will screw up surface active AW, EP and DDI packages. Every polar molecule is competing for the metal surface. I think I remember, if I do correctly, that esters exceeding 20% or something close to that figure, is going to compromise wear protection and damage elastomers.
Yup, it's a balancing act. That's one of the reasons @High Performance Lubricants uses AN's and esters together (as does Mobil), because AN's, while polar, and providing excellent solubility, are less polar than POE, so don't present the same surface competition issues.
 
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They also use to mention in their white papers how the esters they use are so thermally stable and that they don't rely on polymeric thickeners.
Motul for example has the Motul Sport Ester 5W-50, it has like 5% Ester iirc 😅
LOL wasn't that also the case with Nissan's ester oil?

With many ester types I wonder if it's more about the quality/type rather than amount? It's easy to always think more is better.
 
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As someone who has been a long time lurker and recent member I have a question or 2 about what info we can obtain from looking at HTFS. Does the base oil material (POA vs GTL vs G3, etc) give us any insight into how the HTHS and HTFS will differ? Example, does a mostly G3 synthetic show a larger gap between HTHS and HTFS than a GTL or POA base oil? Does the addition of VII’s and their impact on the HTHS differ wildly dependent on the base oil and do certain base oils VII stand up better in terms of others?

Looking at the chart, an oil like Mobil 1 FS 0w40 (POA) shows that the base oil has an extremely low HTFS (2.07) vs the HTHS of 3.6. POA has a naturally higher VI number before any VII are added so does that oil get unnecessarily punished by having a higher VI do to the base oil used. Maybe this has been answered elsewhere, just hoping some the oil geniuses can break it down for me.
 
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As someone who has been a long time lurker and recent member I have a question or 2 about what info we can obtain from looking at HTFS. Does the base oil material (POA vs GTL vs G3, etc) give us any insight into how the HTHS and HTFS will differ? Example, does a mostly G3 synthetic show a larger gap between HTHS and HTFS than a GTL or POA base oil? Does the addition of VII’s and their impact on the HTHS differ wildly dependent on the base oil and do certain base oils VII stand up better in terms of others?

Looking at the chart, an oil like Mobil 1 FS 0w40 (POA) shows that the base oil has an extremely low HTFS (2.07) vs the HTHS of 3.6. POA has a naturally higher VI number before any VII are added so does that oil get unnecessarily punished by having a higher VI do to the base oil used. Maybe this has been answered elsewhere, just hoping some the oil geniuses can break it down for me.

It's due to the 0W-40 having to use a blend of light base oils (~50% 4 cSt) to achieve the 0W-xx winter rating and using a good bit of VII to boost the KV100 to a 40 grade. It gets punished for the high VII load and low viscosity base oils.
 

OVERKILL

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It's due to the 0W-40 having to use a blend of light base oils (~50% 4 cSt) to achieve the 0W-xx winter rating and using a good bit of VII to boost the KV100 to a 40 grade. It gets punished for the high VII load and low viscosity base oils.
Yes, though if you look at Gokhan's calculations, there's quite the range in base oil visc for M1 0W-40 from 7.42cSt (the VISOM version) to 6.17cSt for the SM PAO-based one. The GTL one (current) is 6.92cSt. Castrol Edge 5W-40 is calculated as being 7.03cSt in comparison while HPL Super Car 0W-40 calculates at 7.32cSt.

Some other popular oils would be PUP 5W-30, which calculates at 6.02cSt and M1 EP 5W-30 at 5.77cSt.
 
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Yes, though if you look at Gokhan's calculations, there's quite the range in base oil visc for M1 0W-40 from 7.42cSt (the VISOM version) to 6.17cSt for the SM PAO-based one. The GTL one (current) is 6.92cSt. Castrol Edge 5W-40 is calculated as being 7.03cSt in comparison while HPL Super Car 0W-40 calculates at 7.32cSt.

Some other popular oils would be PUP 5W-30, which calculates at 6.02cSt and M1 EP 5W-30 at 5.77cSt.

That sounds about right after the 4 cSt base oil is blended with some 6 cSt (maybe a drop of 8 cSt), a 12 cSt AN, and then the add pack which can vary from 50-180 cSt.
 
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What does it mean when an oil shows a negative VII number, and therefore a higher HTFS vs HTHS? For example if you plug in Ravenol's SFE you get the following:
oildensity15.6KV40KV100VI (info)HTHSA_Harman indexVIIHTFS (BO DV150)D341 aD341 bKV150DV150BO KV40BO KV100
Ravenol SFE 5W-200.842047.20
8.50​
1602.90
1.0057​
-0.29%​
2.97​
8.140​
3.171​
3.735​
2.884​
48.66​
8.76​

Not the lowest Noack of 8.3 though, which I would have expected to be lower if it's base oil viscosity is as high as it appears.
BTW here's a snip from the SDS that I was able to get from them (revised 08/2021). Pretty high in PAO.
 

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OVERKILL

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What does it mean when an oil shows a negative VII number, and therefore a higher HTFS vs HTHS? For example if you plug in Ravenol's SFE you get the following:
oildensity15.6KV40KV100VI (info)HTHSA_Harman indexVIIHTFS (BO DV150)D341 aD341 bKV150DV150BO KV40BO KV100
Ravenol SFE 5W-200.842047.20
8.50​
1602.90
1.0057​
-0.29%​
2.97​
8.140​
3.171​
3.735​
2.884​
48.66​
8.76​

Not the lowest Noack of 8.3 though, which I would have expected to be lower if it's base oil viscosity is as high as it appears.
BTW here's a snip from the SDS that I was able to get from them (revised 08/2021). Pretty high in PAO.
You are seeing the limitations of the accuracy of this very interesting but not overly useful exercise unfortunately. I applaud Gokhan for the effort, and for sharing his work with us, but this is very much one man's experiment and there are a massive amount of variables that simply cannot be accounted for here, which is why we see stuff like this.
 
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