Group V ester versus Group IV PAO - head to head

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I am getting confused again. Going back to early 1990, myself, my wife, my two dughters and two son in laws have just over 1,000,000 miles on one oil, not one brand but one oil and that is Mobil 1 15W-50. In those one million miles, not one engine problem, the level on the dipstick does not change between OCI, no leaks, no smoke, and gas mileage was always better than EPA estimates, on one little KIA RIO much better.

Since 1992, there was a Honda air cooled, Suzuki air cooled, and a Honda liquid cooled V twin. I will have to best guess the mileage at about 75,000 and the oil was Amsoil 20W-50 motorcycle oil. No oil use, no problems.

Whatever the base of these two oils are, they got it right, and the Mobil 1 is not that expensive($4.40 a quart) of an oil.
 
Originally Posted By: Built_Well
Originally Posted By: Gary Allan
Quote:
I'm still very skittish about
adding primarily PAO-based oils to my car.


You have got to be kidding. It's over 30 years old in "in field" usage. If anything ..some "next evolution" will supersede it ..but none has come to pass at reasonable expense in the cost:benefit end of stuff.

It's not like it's uncharted territory.


Well, cigarettes have been around for a long time, too ;-)

Just because something's been around a long time doesn't automatically mean it's good for you.

Look at Slick 50 and the Lucas Oil Treatment study on this very web site :)

I, and I'm sure many others, just don't know about PAO IV.

I'd like to think good things about PAOs, but cigarette smokers probably think good things about Winston cigarettes :)


Quote:
I thought this site was about honest debate? And I still believe it is :)



..and one would hope "sensible"
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Amsoil definitely does seem to show low engine wear numbers. It's a very good oil when it comes to engine wear. But what about the long-term health of seals? For example, are there any studies that show that engines run on Amsoil over 10 or 15 years maintain their seals as well as engines run on primarily non-PAO oils?

Anectodal evidence is nice, but not conclusive like rigorous scientific studies. Some folks live into their 80's while still smoking cigarettes, but most don't. Get the drift :)
 
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No. You're right. PAO is not a product for you. It will cause all kinds of troubles and just isn't worth it. Anecdotal evidence? Yep, over 30 years of PAO's being on the market and widely used surely falls in that realm. Heck, GM just spec's it because Mobil paid them ..and they don't give a darn passed warranty ..so no skin off their behind.

I often laugh when someone buys the stuff from me ..knowing full well that I'll be telling them that it's not the oil's fault ..but the seal's, when they start leaking.

(shhh- keep that one to yourself, ok??).
 
Be sure to look in the bottle to make sure you got what you paid for. Lol.
 
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Gp II+ with a good add package is all that is needed for 91% of the cars on the road .Look at the uoas . Most change syns at petro oil change intervals.
 
Originally Posted By: Built_Well
Originally Posted By: JAG
BerndV makes another good post, keeping the ship from completely crashing into the shore. Same with Pablo. I don't even need to add input, just agreement.


Maybe so, but they're not defending their position very well. After reading the other forum's
posts about PAOs and esters, I'm still very skittish about
adding primarily PAO-based oils to my car.
It may seem like a position but it is the truth and it's been stated very well, I think. This information comes from motor oil formulators and there is quite a bit of this on various BITOG forums, especially the Science and Technology forums.

There are additives available to formulators to affect seal properties. It's not just the base oils that affect them. Some additives used in all motor oils (like the detergent/dispersant package) affects seal properties. Many oil specifications have seal compatibility tests where tensile strength, hardness, elongation at rupture, etc. must fall within limits.
 
Originally Posted By: Gary Allan
No. You're right. PAO is not a product for you. It will cause all kinds of troubles and just isn't worth it. Anecdotal evidence? Yep, over 30 years of PAO's being on the market and widely used surely falls in that realm. Heck, GM just spec's it because Mobil paid them ..and they don't give a darn passed warranty ..so no skin off their behind.

I often laugh when someone buys the stuff from me ..knowing full well that I'll be telling them that it's not the oil's fault ..but the seal's, when they start leaking.

(shhh- keep that one to yourself, ok??).


ROFL!!!!!!!!! Way to lay on the sarcasm Gary
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Originally Posted By: JAG
It may seem like a position but it is the truth and it's been stated very well, I think.

JAG, what exact truth are you referring to here? That oil blending is complex, that there are many variables involved and many requirements to be met, that are all sorts of compromises and give-and-take decisions to be made, that any oil needs to be a blend of more than one base stock type to function effectively, that no one base stock type has ideal characteristics if it were to be used as a finished motor oil?

Let's just take them all as a given, since frankly those things are probably known and let's even say reasonably well understood to most of us here, and address the fundamental question being asked: if you have a choice between a primarily grp IV oil and a primarily ester (POE, for example) oil, with all other factors equal - or, more precisely, with all other factors having been equally well optimized for the chosen blend of base stocks - what oil will give you the highest performance capabilities overall?

What do you think?

I know it's complicated, it depends on the application, the OCI, the conditions, and of course the particular product, but still, overall, what is your opinion? You know that POEs have some significant advantages over PAOs, the polarity/film strength argument being a common one and my personal favorite; and at the same time you know they are much more expensive, dis-incenting their use among mass-market blenders.

Do you really believe the predominantly-PAO blenders are creating the best possible oils regardless of cost? What is the possibility in your opinion that at least some of the ester-based oils are better products overall? Is the margin of error on your opinion too great to make a judgement either way? Is the application variability greater than the product performance variability? I'm curious what you think.
 
Originally Posted By: glennc
JAG, what exact truth are you referring to here?
That oil blending is complex, that there are many variables involved and many requirements to be met, that are all sorts of compromises and give-and-take decisions to be made, that any oil needs to be a blend of more than one base stock type to function effectively, that no one base stock type has ideal characteristics if it were to be used as a finished motor oil?
Yes, that's it.
Originally Posted By: glennc
Let's just take them all as a given, since frankly those things are probably known and let's even say reasonably well understood to most of us here, and address the fundamental question being asked: if you have a choice between a primarily grp IV oil and a primarily ester (POE, for example) oil, with all other factors equal - or, more precisely, with all other factors having been equally well optimized for the chosen blend of base stocks - what oil will give you the highest performance capabilities overall?
Of those two choices, my opinion is that the primarily PAO based motor oil is overall best. The biggest reason is because I think PAO deals better with moisture-rich blowby than POE does (hydrolytic stability).
Originally Posted By: glennc
Do you really believe the predominantly-PAO blenders are creating the best possible oils regardless of cost? What is the possibility in your opinion that at least some of the ester-based oils are better products overall? Is the margin of error on your opinion too great to make a judgement either way? Is the application variability greater than the product performance variability? I'm curious what you think.
I think that the predominantly PAO based oils could be improved if cost became no object.

I'm sure that some ester-based oils are better overall than some PAO-based oils. IMO, an example of a likely-to-beaten PAO-based oil is Lubromoly 0W-40. Its response to ~320F temps in the presence of a penny was to dissolve a significant amount of copper while some other synthetics I tested did not dissolve such large amounts of copper even when the test lasted much longer.

Check out this thread about alkylated napthalene, especially the link in the first post. http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=787833&fpart=1
 
I too agree with JAG. I'm kind of shocked this thread has continued on so long.

Neither 100% PAO or 100% ester based oils are desirable IMO. This is why most of the best oils in the world are majority PAO with esters mixed in.

JGR, M1, Shell Racing oils, Elf F1 oils etc etc. are all majority PAO with some % ester. Ester selection is also important. Many esters are not ideal either.
 
For those wishing to follow, alkylated napthalenes (A.N.) are in Group V, and are formed by the reaction of olefins with napthalene.

A short quotation:

"ExxonMobil Chemical offers innovative Group V alkylated naphthalenes under the trade name Synesstic(TM) blendstocks. These novel, highly stable Group V
blendstocks are formed by the reaction of olefins with naphthalene.

"Alkylated naphthalenes offer the hydrolytic stability of a PAO and excellent additive solubility of an ester They also can help improve additive system efficacy
because they are less polar than esters. Lubricants blended with Synesstic(TM) AN products provide increased hydrolytic and thermal/oxidative stability, resulting
in increased oil service and longer equipment life."

...

[Again, Synesstic is a trade name for Group V alkylated naphthalenes.]

"In the Timken Four Ball test, a VG220 oil containing PAO, Synesstic(TM) 5 and an additive package showed significantly less wear under heavy loads than a
formulation based on PAO, polyol ester and the same additives. The extra wear protection is believed to result from the benefit of alkylated naphthalenes,
allowing additives to function at their full potential."

# # # # #

POE = PolyOl Ester (Group V)

PAO = PolyAlphaOlefin (Group IV)

Link to the 3-page article:

http://findarticles.com/p/articles/mi_qa5322/is_200611/ai_n21405799
 
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The only real advantage I see with group IV and V oils is that they may last a bit longer...I do not like the high FE levels that are common to group IV/V synthetics.

I'm convinced that group II+ or Group III oils are just as good at protecting the engine as long as they are changed at the correct interval...
 
Originally Posted By: whitesands
The only real advantage I see with group IV and V oils is that they may last a bit longer...I do not like the high FE levels that are common to group IV/V synthetics.


Maybe I missed that thread.
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Superb post Glenn!

Just to add another variable, there are dozens of different POEs available for lubricants and they can vary greatly in performance. For example, POEs can be made quite hydrolytically stable by branching the acids at the alpha or beta carbons, and such acid branching can also improve oxidative stability, polarity, and cleanliness (coking). On the flip side it reduces the VI and lubricity and can raise the pour point and price. The degree of these changes depends on the length and position of the branches as well as the ratio to the other linear acids. Everything you do involves compromise, and balancing the properties to the intended application is extremely complex.

Trying to characterize the performance of a motor oil strictly by its base oil composition is an entertaining but academic game.

Tom NJ
 
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