Why is a Group IV usually thought of as better?

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Just wondering. I know that a Group IV has a lower pour point for the most part, but with Group III oils vastly improving what makes a Group IV better?
 
PAO, or group IV, does not have any of the petroleum by-products, such as waxes, in it since it is synthesized.
 
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Just wondering. I know that a Group IV has a lower pour point for the most part, but with Group III oils vastly improving what makes a Group IV better?




Less shearing (High HT/HS) means less crystallization. Hence stays in grade... Once the viscosity modifiers are used up in grpIII, you'll see the difference
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PolyAlphaOlefin is a pure chemical molecule, requiring less additives. Group III oils are made of hundreds, maybe thousands of different petroleum molecules, requiring more additives. The pure chemicals can be made to exacting standards for stability and lubrication.
 
What's the longest OCI claim (by manufacturer) for a known pure Grp III ? This may also shed light on the performance diff. in Grp III and IV/V. Thanks!
 
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Do we know of any 100% pure Group IV oils that have no Group II/III added?
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Amsoil(non XL) and Royal Purple come to mind




I have to disagree. Just because Amsoil is mainly PAO doesn't mean that some other groups are not used in various amounts.
 
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Do we know of any 100% pure Group IV oils that have no Group II/III added?
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Amsoil(non XL) and Royal Purple come to mind




I have to disagree. Just because Amsoil is mainly PAO doesn't mean that some other groups are not used in various amounts.




Ahh...I read it too fast, he said 100%....yep in that case you are right.
 
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I actually doubt that ANY PCMO is 100% anything. Here is Amsoil blurb about formulations: http://www.amsoil.com/faqs/faq8.aspx

I believe that PAO does use petroleum products to build the oil up. The way I see it, group III takes a lower group oil and turns it into a group III through hydrocracking and other processes while a group IV PAO takes individual parts of conventional oil and uses them to build up to a group IV. So, for group III, you start with something less desirable and get rid of impurities and less desirable components (waxes, etc.), while a group IV starts with nothing and only puts in desirable components. A conventional oil can become nearly pure and exhibit great qualities after the process because most of the "bad stuff" is removed while a PAO should not have any of the "bad stuff" in the first place so it should theoretically be better. This does not take into account any issues with additive solvency, which group IV does not do as well as group III does. This is one reason why you won't see 100% PAO in a PCMO oil. Some other group is needed in at least a small amount to solve some of the additives.
 
What have we here?? Reading that link that cfromc provided, it looks like Amsoil may be in the same non-committal camp as M1 on describing what base stock comprises their synthetics. Amsoil says the XL is "based" on grp III and that the others are "based" on PAO - but then they go on to say they'll do propietary combinations to get the best oil performance for the application. It almost seems like they're admitting the combination of grp III and grp IV/V - when they describe these base stocks as being similar to additives, and then state that just as additives are combined for best performance, so are they're base stocks. Am I seeing things here?
 
According to Amsoil, they have been combining different types and Groups of base oils for years to get the properties that they desire in their finished lubricants. No oil is going to be 100% PAO base oil, just like Redline is not 100% POE.
 
100% PAO would be great marketing, but put in better terms it still has almost the exact effect.(eg) "BASED" on 100% PAO. Less money lost durning production and no profit is lost while "bleinding" the groups?
Why waste money when all of the other companies fork up more and more cash "improving" their formulas.
Possibly because 100% PAO is not nessesary for their own performance standard to be achieved?

That is just ONE theory of mine, that has NOT been discussed in this post. All others have been discussed over and over.
 
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PAO and Group 3 cannot solubize the additives. Even Group 2 is borderline from what bruce381 once said here. Full Synthetics as defined in the U.S. cannot have Group 1 or 2 as BASESTOCKS but they can have Group 1 as additive carrier oil to solubize the additives. Group 5 can solubize the additives without the drawbacks of Group 1.
 
"solubize?" Does that mean additives won't dissolve in grp 3 or PAO but will in grp 1? and, therefore, are easily seperated from the oil?
 
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