Is PAO (Group IV) no longer important?

facility1 said:
if i am reading this correctly, a small blend of say 10% group 4 and group 3+ would make a ideal engine oil ,,like Havoline pro-ds and Pennzoil platinum etc?
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Typically it's the Gr5 such as AN/Ester which are added in smaller amounts in order to counteract seal hardening and provide some solvency etc. PAO or Gr3+ would account for the majority (70-90%) of the base oil composition especially with regards to the 20 grades and below.

The additives become more important than base oil once you get to the 20 grades and below as well.
 
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930.engineering said:
Au contraire. Solubility is actually a non issue with PAO since no
blender never uses 100 % PAO and it's common to blend it with
ester and/or AN. Every blender will tune the 'sweet spot', say the
final product's aniline point which means an appropriate solubility.

In reality PAO means a PAO/AN/ester blend. The most relevant if
not the only disadvantage: $$$$$$$$$$$$$$$$$$$$$$$$$$$$$ !!!


ps:
Some blendes may add some group I/II on their less pricy products.
.
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You proved my point. Nobody uses 100% PAO since it has solubility issues. You HAVE to blend it with something else where as group III does not need to be blended with something else. (though some blenders do anyway) A group III / ester / AN blend will perform as good or better than PAO / ester / AN in most anything other than negative temperatures or extremely light racing oils.

Even oils that use some PAO and/or ester/AN can still have some group I content. Most additive packages are blended in a group I base oil so there's going to be some group I in most all oils. Some higher end blenders order their additive packages blended in a group III base.
 
camrydriver111 said:
I remember 10 years ago there was a lot of discussion about which oil has the most PAO. People's goal was to use the oil with the most PAO because performance was better than Group III.

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

I have been away from the oil scene for a few years. Why has Group IV fallen out of favour? Is there new research to suggest it doesn't protect as well as Group III?
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Some of the trends on here over the years have to do with...................

................whatever Mobil is doing currently.


All hail XOM, provides everything.
 
For anything but extreme low temp performance no. Doesn't seem like Mobil is using much pao in their newly released 1000 hour 15w-40 and 2000 hour 5w-40 which i made a post about here https://bobistheoilguy.com/forums/threads/new-mobil-delvac-extended-performance-oils.375610/

Some argue you need pao for oxidation resistance for long intervals though the 5w-40 doesn't seem to have much if any pao judging by the numbers so even for that pao isn't really needed like before. Advanced group 3 performs extremely well.

HPL also has CC versions of their atf's for ultra low temp performance that uses pure pao. Only real use case for pao nowadays.
 
RDY4WAR said:
You proved my point. Nobody uses 100% PAO since it has solubility issues. You HAVE to blend it with something else where as group III does not need to be blended with something else. (though some blenders do anyway) A group III / ester / AN blend will perform as good or better than PAO / ester / AN in most anything other than negative temperatures or extremely light racing oils.

Even oils that use some PAO and/or ester/AN can still have some group I content. Most additive packages are blended in a group I base oil so there's going to be some group I in most all oils. Some higher end blenders order their additive packages blended in a group III base.
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How about runtime, for example HPL has the PCMO line (Group III) and the Premium Plus line (Group IV?), I've seen the two threads here from wwilson running really long oil change intervals but that wasn't on the standard PCMO.
 
Cujet said:
The claim has been made that AN's are better lubricants, and require lower levels of additives.

I have to wonder, as PAO's real claim to fame is the ability to perform properly from -60F to +500F. AN's are not for severe cold, as they don't flow at all under about -30F. And they are not as resistant to coking on turbocharger hot sides as PAO.

As always, many of us are not operating in Antarctic temperature extremes, and don't run 75 pounds of boost in our daily drivers.
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What are AN’S?
 
4WD said:
How do they do that better than - say Grp3 ?
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Put amsoi SS or Redline up against any of the lower tier oils you find a walmart Pennzoil M1 Valvoline ETCand Amsoil comes out on top everytime . Now with that being said most eveyday vehicles will have a long healthy life using the lower quality Grp3 Oils you can find at your walmart advanced auto . But if u want the best and extend OCI safely you gotta go Grp4 motor oils
 
MalibuRam65 said:
Put amsoi SS or Redline up against any of the lower tier oils you find a walmart Pennzoil M1 Valvoline ETCand Amsoil comes out on top everytime . Now with that being said most eveyday vehicles will have a long healthy life using the lower quality Grp3 Oils you can find at your walmart advanced auto . But if u want the best and extend OCI safely you gotta go Grp4 motor oils
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That’s how?
 
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.
 
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.
 
4WD makes a good point, we can't really tell on sds or blackstone tests accurately,,just a generalization at best,its a secret what the blender/manufacture really put in base oils and additives ,though some are more transparent than others,,have to admit HPL is really good at sharing knowledge of their excellent product line,schaeffers,torco amsoil to mention also up front about their lubricants ,,,,,some of major oil companys,,proprietary vs consistancy and continual changing of formulated product lines certifications etc , would be nice if more lube/blenders/manufactures give more real information on the products they sell for our $$$$$ vehicles,,we want to know...
 
cheesepuffs2 said:
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.
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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
 
I recently ordered 18 liters of CVT fluid from a foreign producer who makes it using GTL and an AN.

Unless some of the posts I read on their oil forum are incorrect, it seems GTL is better for transmission fluid:

Translated comments:
"The working environment of the gearbox is much better, and the difference is very big compared with the engine. For us ordinary car enthusiasts, the oil temperature of the gearbox cannot exceed 150 degrees. Generally it is around 100°C. Looking at the engine oil, the internal temperature of the engine can be as high as thousands of degrees. The hottest place near the piston ring is about 400°C.

The transmission oil base oil is required to be pure with as few impurities as possible. At this point, pao base oil is not as good as gtl base oil. GTL base oil is 99.99% linear alkanes with very high purity and completely free of sulfur and phosphorus. Even PAO can't do it. However, PAO has stronger high and low temperature performance and high temperature oxidation resistance, but there is no such high temperature in the gearbox.
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Viscosity index is higher than red line. CCS is lower.

GTL seems like a winner.
 
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