Group III synthetics & Viscosity Index Improvers?

[silverbullet]

Does group III synthetics contain Viscosity Index Improvers? Or are they like Group IV and V synthetics that do not contain VII's?

 

[Max_Wander]

lol heeerrre we go!

 

[silverbullet]

i don' see what's so funny. i did a search and did not find an answer to my question. nor is this a question that is beating a dead horse like "5w20 or 5w30?" "dino vs. synthetic?"

 

[G-MAN]

Every Group III synthetic made will have some VI improvers.

Group III base oils, unlike PAO, are made in a relatively narrow vis range, in the 4.0 to 8.0 cSt range, which means to make virtually any multigrade Xw30 or Xw40 motor oil VI improvers will have to be used--that or other type base oils will have to be blended in as well.

 

[silverbullet]

Thank you G-Man for your response.

 

[Ron AKA]

Still have my link saved from the last post. See this link which has the VI of the base oils, and you can see they all need a lot of help to get up to 165-170 or so.

http://www.chevron.com/products/prodserv/BaseOils/comp_light.shtml

Groups I&II are conventional, while Group III and IV are synthetics.

 

[bruce381]

Quote:

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Every Group III synthetic made will have some VI improvers.

Group III base oils, unlike PAO, are made in a relatively narrow vis range, in the 4.0 to 8.0 cSt range, which means to make virtually any multigrade Xw30 or Xw40 motor oil VI improvers will have to be used--that or other type base oils will have to be blended in as well.

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bruce

 

[cfromc]

Ron, Group III's are only synthetic in a court of law. You could say the definition is arguable but from where I sit, they are just highly processed conventional oils.

 

[Ron AKA]

Quote:

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Ron, Group III's are only synthetic in a court of law. You could say the definition is arguable but from where I sit, they are just highly processed conventional oils.

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The law guys must know their oil. If you check the link I posted you will see the viscosity index for the Chevron and Petrocan Group III's is better than the Chevron PAO group IV. So it is the PAO that needs more VII, not the other way around.

 

[cfromc]

So? That somehow means that conventional oil becomes synthetic?

 

[Nebraskan]

And I always thought that synthetics, like Amsoil and GC were group IV and needed no Viscoisity Index Improvers. Seemed to me that Amsoil advertised, or I got the understanding somehow that they used no VI improvers. Sheesh.. live an learn and get smarter! ... think I'll have a cold one..

Anyone else??

 

[Ron AKA]

Yes with some effort, what comes out does not look much like what went in.

 

[JHZR2]

Quote:

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Every Group III synthetic made will have some VI improvers.

Group III base oils, unlike PAO, are made in a relatively narrow vis range, in the 4.0 to 8.0 cSt range, which means to make virtually any multigrade Xw30 or Xw40 motor oil VI improvers will have to be used--that or other type base oils will have to be blended in as well.

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What about the Shell XVHI basestock, as used in rotella synthetic and to some extent in helix Ultra viscosities??? IIRC, all of these are at least 40wt (unless there is a heavy 30wt in there).

Are you saying theyre all chock full of VII, though theyre made as high performance and HDEOs? I think the helix ultra has PAO mixed in (so I might have answered my own question there), but what about Rotella syn 5w-40???

Thanks,

JMH

 

[Ron AKA]

The best VI's I've seen for a base oil are the Visom ones from ExxonMobil - 140-144. However flash point is not so "hot". These should not need much VII, and they are a Group III.

http://www.exxonmobil.com/Germany-English/Basestocks/PDS/Pds_Files/glxxenbskemvisom.pdf