"Group-ese" and "order"

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Okay ..I was never a good texted based student. The lecture(r) was my principle tool for learning. I don't integrate some things well and need to apply appropriate "analogs" for assimilation.

Here I need to get a grip on the oil groups.

Group I appears to be normally refined oil.

Group II appears to use a catalyst to reform the moledules. There also appears to be a "II+" element to this group.

Group III is allegedly an advancement or further extension of this catalytic process (some said longer and hotter).

Group IV - never really mentioned much so I haven't a clue.

Group V - allegedly used for additives = why? Too expensive to produce as a stand alone lubricant? Unsuitable for use as one?


So ..I've seen threads that claim that Group II base stocks are superior to Group III ..yet I also hear exactly the opposite. Here a Group II gets a thumbs up over a Group III diesel oil. So I guess the Group III diesel oil producer just spent all the extra catalyst time to detune their oil down to below the inherant properties of the, in this thread, superior Group II base stocks. As you'll also see in this thread ..the Group II is referred to as a PAO ...which everyone appears to hail as the greatest thing in the world ...on the other hand ..in another thread "Mobil I is rumored to be Group III" and it implies that the Group III is NOT PAO. So someone also, in this case, and for no apparent reason "detuned" their oil by spending too much time in the catalyst (using the advanced process) to escape the comfort of PAO and evolve it into an inferior product which you all critique.

What is wrong with this picture??? Now I don't learn at a rapid rate ...but someone here has to admit that there are a whole lot apparent conflicts in this "Group heirarchy" that don't follow normal, sensible, rational.

To index "me" ..I can understand "mesh currents", "high Z", harmonics, and a host of other various complex processes and functions ..but this "groupese" just isn't falling into any sound rationale~.


Can any of you true oil geeks explain this lack of apparent sensibility ..or rather provide me with the "special education"
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to align this mess into order?

btw- I've asked for this several times ...and although I've gotten some "skinny" answers to specific elements ..no one appears to want to tackle this. Links to other vendor sites only appear to add more conflict.
 
Group IV is PAO, polyalphaolefin. It is produced using a catalyst, hydrogen, heat, and pressure. The feedstock (the raw building blocks) is ethylene gas, and these small gas molecules are "built up" to form larger oil molecules. This is called polymerization. As you pointed out correctly, Group II and III are produced by a catalytic process, too, but the feedstock is the VGO (vacuum gas oil from the crude oil distiller), and the catalytic process used to produce these base oils is not polymerization, but isomerization. The oil and other molecules contained in the VGO are converted into fully saturated hydrocarbon molecules, yielding a chemically pure base oil.

Group V is esters and other base oils that don't fall into any other category. Some additives are esterfied, but generally when we talk about Group V, we are talking about ester base oils
 
Okay so this assertion here
quote:

I really doubt a group III diesel oil will outperform in all respects any fully formulated PAO like the AGIP and others to include the new Amsoil .

when the site clearly states that it uses pure Group II base stocks .. is incorrect. You can now see why someone ignorant of "groupese" would take the word(s) in that post and find it in conflict with your statements.

quote:

Group IV is PAO, polyalphaolefin.

So ..when someone, like yourself, would say something like "...Group III VI is well into PAO territory" ..you are actually saying, "the properties (or rather statistical characteristics) of (this) Group III oil compare to the properties/statistical characteristics of a PAO (and unsaid, but only assumed) yet have NONE of its chemical composition properties (note the missing link). Therefore a Group III may in fact mimic many of the apparent properties of a PAO in terms of performance ..but not substance.

[ May 29, 2004, 03:40 PM: Message edited by: Gary Allan ]
 
quote:

Originally posted by Gary Allan:
"the properties (or rather statistical characteristics) of (this) Group III oil compare to the properties/statistical characteristics of a PAO (and unsaid, but only assumed) yet have NONE of its chemical composition properties (note the missing link). Therefore a Group III may in fact mimic many of the apparent properties of a PAO in terms of performance ..but not substance.

Exactly. Generally, what we compare between Group III and PAO is performance. They are not the same in substance, but as catalyst technology advances, Group III base oils are getting closer and closer to mathcing the "performance and specs" of PAO in virtually every category.
 
Excellent explanation G_ManII.

Gary. FWIW, Group III oils are excellent for advanced ATF's, light manual transmission fluids, and low viscosity motor oils, primarily because the current isomerization technology yields the lighter fluids. Now as technology develops in this area, higher viscosity fluids will emerge for HDEO's and gear lubes, greases, etc. So technologically speaking, Group III is just a half-step below Group IV oils in performance. Additive technology has resolved the additive solvency problem just as they solved it for Group IV oils when they came onto the market.

One of the major problems with the whole Group III issue is this: Manufacturers and blenders are attempting to pass off Group III fluids as synthetic fluids and pricing them as if they were true Group IV and Group V oils. Group III oils are NOT as expensive to make as Group IV, V oils.
 
Don't forget G-III that are not Hydroprocessed, but wax isomerates. Shell's XHVI, for instance. Also there are G-Vs that are not esters, G-V also includes "others". POE Gas-to-Liquid fluids fall into this catagory.
 
toocray2yoo ..there are those that assert, in spite of the radical reformation that takes place, that Group III oils are psuedo synthetics. Or SINO "Synths in name only".

The distinction is minor in practical use. The main objection is the like pricing to more expensive PAO offerings. What's not factored in is that the PAO offerings ..that the Group III oil are on par with pricewise (and mostly performance-wise) are also sold by the primary producers of such stuff ..hence they have a semi-monopoly on the product. The other offerings that have their own unique niche (like GC) are WAY more expensive then any common Group III synth wannabe (other's words) ..so it discounts this attitude to a degree.

I haven't a clue about Havoline.
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Forgetting Havoline, does every oil that's all GRPIII automatically labled "Syn"? Or is there a GRPIII that doesn't hang the Syn tag on the bottle?

I suppose that's the gist of it, huh?

I understand the performance "catch-up" that's taken place, hence, my imminent abandonment of M1 for Havoline. Interesting Mobil & Co. seem to keep that their little secret. Who besides BITOG (or similar venues, if there ARE any) would ever know any of this?
 
Quote:
Group III oils are excellent for advanced ATF's, light manual transmission fluids, and low viscosity motor oils, primarily because the current isomerization technology yields the lighter fluids.


Well that might explain why the MSDS for Synpower 20w50 showed mostly (like about 85%) PAO, while the others were mostly Group III (older SL version, think SM shows more PAO in the other grades).
 
Seems also the potential [best] oils can be a blend of the two or three base stocks. For automotive type gas and diesel engines to stir up the pot!
 
Originally Posted By: Gary Allan
Yes ...let's see if we can get you to chase your tail and end up back here again
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Worse yet, ever have multiple tabs open on BITOG threads and hurriedly post a response to one thread in a different thread of a totally different topic?
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