Chevron and Iso -Syn and Grp II+

[Winston]

OK, so I was at my local chevron station the other day, reviewing their oil supplies like any good Bitoger would do, and I noticed something. Only the 5W20 and 5W30 oils had the ISO-SYN lable on the bottle. They had 10W30, 10W40 and 20W50 chevron oils. I did some research here and found out the following.

I think the ISO-SYN lable means that the base oil is Chevron's "5R" base oil. This is a Grp II+ base oil.
Chevron Base Oils

This base oil is only used for making 5W20 and 5W30 oils. For the 10W30 and 10W40 oils, the 100R base oil is used which is not a grp II+ oil. Hence it is not "Iso-Syn".

Chevron Oil Blends

So, are Chevron's 5W20 and 5W30 oils better than their heavier weight oils? Will Chevrons 5W oils tend to keep your engine cleaner than Chevrons 10W oils?

 

[TR3-2001SE]

I have some of the 10w-30 at home and I think it is labeled ISO-SYN. Will check and report back tomorrow. I have had it awhile so maybe this is a change.

 

[vwoom]

I've posted this concern twice before about of the sudden lack of IsoSyn labels on the heavywts 10w30s, 10w40s & 20w50s.

For a brief time early this year I also noticed that quite a few 5w20s & 5w30s qts at several Kragens and AZ lacked the logo as well..within the industrywide SL to SM transition period. But as mentioned above, only the lightwts now sport this label.

What's confusing though is why the latest boxes of 10w30s, 10w40s & 20w50s Supremes still sport the Iso-Syn tag while on the qts themselves do not..?

Now I'm stocking up on SM GF-4 5w30s(presumably as Mo rich as SM Havo)to dilute my 25qts of SL/CI-4+ A3/B3 Delo 15w40(Mo rich & moreso Ca rich)..to attain a thick 30wt akin to a popular 12 Cst oil.

[ October 31, 2005, 03:00 PM: Message edited by: vwoom ]

 

[Winston]

At the gas station I was at, there were SM versions of all the oils and there were some SL versions. ALL 5W oils said iso-syn and NONE of the 10W oils said ISO-SYN. This agrees with the Chevron links that I showed above. OTOH I wonder how that will affect the performance of the 10W oils?

 

[bulwnkl]

The Chevron guy on this board discussed/explained this some time in the past month or thereabouts. Go searching some more. IIRC it has to do with suppliers/packagers among other things.

 

[vwoom]

quote:

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Originally posted by Winston:
OK, so I was at my local chevron station the other day, reviewing their oil supplies like any good Bitoger would do, and I noticed something. Only the 5W20 and 5W30 oils had the ISO-SYN lable on the bottle. They had 10W30, 10W40 and 20W50 chevron oils. I did some research here and found out the following.

I think the ISO-SYN lable means that the base oil is Chevron's "5R" base oil. This is a Grp II+ base oil.
Chevron Base Oils

This base oil is only used for making 5W20 and 5W30 oils. For the 10W30 and 10W40 oils, the 100R base oil is used which is not a grp II+ oil. Hence it is not "Iso-Syn".

Chevron Oil Blends

So, are Chevron's 5W20 and 5W30 oils better than their heavier weight oils? Will Chevrons 5W oils tend to keep your engine cleaner than Chevrons 10W oils?

---

Ahhh...but how can you account for IsoSyn Delo 400, a heavier Chevron oil than Supreme 10w30/40s and considerably moreso than it's 5w20/30s cousins?

 

[Ray H]

I'm not sure the 10W-40 and 20W-50 conventional Chevron Supreme PCMOs were ever listed as "ISOSYN" on the bottles, even in their "SL" iterations. As to the 10W-30 "SM" formulation, the question may be more theoretical than practical. That viscosity grade still carries an extremely robust flash point for a "conventional" - +450 degrees F. That fact implies both a very oxidatively stable fluid (for varnish and gelling protection) and equally likely, at least Group II base stocks - probably just barely shy of Group II+.

 

[MarkC]

Chevron oils are at least Group II.

 

[vwoom]

I'm not sure the 10W-40 and 20W-50 conventional Chevron Supreme PCMOs were ever listed as "ISOSYN" on the bottles, even in their "SL" iterations.

The heavy wts 10w30,10w40 & 20w50 pcmos used to be Iso-Syn..am pretty sure of that. In fact I have but 2qts of the remaining case of SL 10w40s Supreme w/ the IsoSyn label I bought exactly a year ago, sitting in the trunk of the 190E as top-off.

Right after the introduction of API SM sometime late last year that the IsoSyn label started to disappear..from the thicker 20w50s and down to 10w30 presently.

 

[Winston]

quote:

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Ahhh...but how can you account for IsoSyn Delo 400, a heavier Chevron oil than Supreme 10w30/40s and considerably moreso than it's 5w20/30s cousins?

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Yup. You've got me on that one. I see that the new Delo 400 came out in June 2004, so maybe it is a newer base oil than the 5R listed in my other links. Still, it seems like the base oil used for Chevron's higher weight PCMO's is not the Iso-Syn (Grp II+) base oil.