Is PAO (Group IV) no longer important?

[OVERKILL]

GTL and grp III come in a limited number of viscosities (all pretty low), while PAO can be made to pretty much any viscosity you like. So if you are making high viscosity stuff you are limited in the amount of GTL and GRP III you can use. And if you use it, the Noack will get worse

Yes, exactly, Shell has a pretty narrow slate of GTL base oil viscosities, while Mobil's slate of PAO options is massive, and then there is mPAO on top of that.

 

[4WD]

Yes, exactly, Shell has a pretty narrow slate of GTL base oil viscosities, while Mobil's slate of PAO options is massive, and then there is mPAO on top of that.

Yep - mPAO in industrial gear boxes does HD work for a long time …

 

[OVERKILL]

For PCMOs, PAO is basically going obsolete with the rise of GTL, no? My understanding is that GTL is very close in cold performance to PAO but at a significant reduction in cost, which to me sounds like it's never going back.

No, GTL is not close in straight-up cold temp performance as it still requires PPD's, but since it has less wax in it than conventional Group III, it needs less in the way of PPD dosing when compared to PAO.

GTL 4 has a pour point of -30C, GTL 5 has a pour point of -24C, and GTL 8 has a pour point of -15C
PAO 4 has a pour point of -60C, PAO 5 has a pour point of -57C, and PAO 8 has a pour point of -48C

 

[michael007]

No, GTL is not close in straight-up cold temp performance as it still requires PPD's, but since it has less wax in it than conventional Group III, it needs less in the way of PPD dosing when compared to PAO.

GTL 4 has a pour point of -30C, GTL 5 has a pour point of -24C, and GTL 8 has a pour point of -15C
PAO 4 has a pour point of -60C, PAO 5 has a pour point of -57C, and PAO 8 has a pour point of -48C

Interesting how just a little bit of PPD brings GTL to the same pour point as PAO 8

For the CVT fluid I got, it's:
-0.4% PPD
-86% GTL
-17% additive

 

[OVERKILL]

Interesting how just a little bit of PPD brings GTL to the same pour point as PAO 8

For the CVT fluid I got, it's:
-0.4% PPD
-86% GTL
-17% additive

View attachment 192049

Yup, though I assume you appreciate that PAO 8 is heavier than that product, so you are likely looking at something blended with GTL 5 based on the Noack and VI.

The problem with PPD's of course is that they degrade in service, which is why oils are allowed to slip a Winter grade in service.

 

[cheesepuffs2]

I'm about this close to running cheap 5w-20 oil in my wife's car for the winter as it's winter oil change is usually around 3,500 to 4,500 miles due it fuel contamination and it being a gdi engine.

What are you running currently?

 

[loneryder]

Recently I was wondering what Dave at HPL thought about GTL base oils. Do any of you guys who visited him happen to know?

 

[oil pan 4]

What are you running currently?

The good stuff but it's only about $30 for 5qt so I haven't been super motivated to go cheap.

 

[cheesepuffs2]

The good stuff but it's only about $30 for 5qt so I haven't been super motivated to go cheap.

What is "the good stuff"?

 

[jia_di]

Yup, though I assume you appreciate that PAO 8 is heavier than that product, so you are likely looking at something blended with GTL 5 based on the Noack and VI.

The problem with PPD's of course is that they degrade in service, which is why oils are allowed to slip a Winter grade in service.

There is no high temperature inside the gearbox, which makes it almost impossible for the pour point depressant to be thermally decomposed, and it is impossible for tens of thousands of kilometers to make the pour point depressant sheared and invalidated.

 

[jia_di]

Interesting how just a little bit of PPD brings GTL to the same pour point as PAO 8

For the CVT fluid I got, it's:
-0.4% PPD
-86% GTL
-17% additive

View attachment 192049

Endu CVTF（恩渡CVTF

ACEA list

You can find information on engine oils for "ENDU" in the ACEA Corporate Member Directory. It was made by a Chinai lubricant company. They only use Shell's GTL, Mobil mPAO and Mobil alkyl naphthalene base oils when manufacturing transmission oils. Mineral base oils are not used. Their engine oils are even more impressive, using only category 4 and 5 base oils. (Mobil and Chevron PAO, Mobil mPAO, Mobil NP451 polyol ester, Mobil alkyl naphthalene) Additives are the top composite additive packages from Infineum、Chevron and Afton.

 

[jia_di]

没错，壳牌的GTL基础油粘度非常小，而美孚的PAO选择范围很大，除此之外还有mPAO。

GTL 87.6%，PDD 0.40%
pour point ＜-57℃（＜-70.6℉）
Brookfield Viscosity@-40°C（-40℉）,
cP 6940

 

[jia_di]

是的-工业齿轮箱中的mPAO确实HD工作了很长时间...

Dual clutch transmission fluid using Shell GTL and Mobil mPAO, 0% Viscosity Index Improver.
Almost zero shear loss was achieved（DCTF-H @1.85%&[email protected]%）

Endu DCTF-H

endu DCTF-L

 

[jia_di]

是的-工业齿轮箱中的mPAO确实HD工作了很长时间...

ENDU 75W-90（GL-4、GL-5）
mobil mPAO,38.68%
shell GTL,56.02%
VM，0%
KRL Shear loss rate -0.13%，-0.13%

 

[michael007]

There is no high temperature inside the gearbox, which makes it almost impossible for the pour point depressant to be thermally decomposed, and it is impossible for tens of thousands of kilometers to make the pour point depressant sheared and invalidated.

@jia_di is the one who sold me the oil.

He's a teacher, motivating his students to be interested in lubrication and his side hustle is running a distribution company called "Motor oil Society" (which does not ship outside of his country at this time).

If anyone has tough questions for him, I have no doubt he'll love to answer.

 

[OVERKILL]

There is no high temperature inside the gearbox, which makes it almost impossible for the pour point depressant to be thermally decomposed, and it is impossible for tens of thousands of kilometers to make the pour point depressant sheared and invalidated.

That's of course going to depend on the application, as to how hard on the PPD's it is.

 

[Triple_Se7en]

I'm about this close to running cheap 5w-20 oil in my wife's car for the winter as it's winter oil change is usually around 3,500 to 4,500 miles due it fuel contamination and it being a gdi engine.

You're using 5w20 in a Heavily modified 1984 6.5L suburban (to this day)?
If that's your ride, then your wife's vehicle never got listed in your signature.

 

[Jackson_Slugger]

...
Now people are telling me that the only difference between a semi-synth and a full synthetic is $3 to $4 per quart.

'''

I'm not sure where people are seeing this sort of price gap between blends and full syn, I can't find any. Maybe more like $1-3 a jug at best and syn usually has better rebate offers...

 

[oil pan 4]

What is "the good stuff"?

Pennzoil platinum
It's the best oil for the least $.

 

[michael007]

That's of course going to depend on the application, as to how hard on the PPD's it is.

Unless I'm mistaken, I think he's basing his comments on the KRL test results.

Some info for those learning like me:

CEC L45-A-99 - The KRL Tapered Roller Bearing test is becoming the test of choice of many OEM’s around the world, as it is considered the most severe and offers the best correlation to actual field performance. Test oil is run in a fitted tapered roller bearing for 20 hours under design load. Before and after viscosities are compared for percent viscosity loss.

The graph below shows a 12.6% reduction in viscosity shear loss from a shear unstable oil to a shear stable oil as tested in the KRL Tapered Roller Bearing test.

------------------------------------------------------------------------------

The dual clutch ATF is made from GTL (87.7%), mPAO (1.5%), PPD (0.3%) and when tested:

Almost zero shear loss was achieved（DCTF-H @1.85%&[email protected]%）

His second example was the 75W90. GTL (56.02%), mPAO (38.68%), PPD (0.4%) and when tested:

KRL Shear loss rate -0.13%，-0.13%