Synthetic Qualifications

[ndfergy]

Often wondered but never asked: what qualifications and or minimums of the base oils are required to be allowed to be marketed as synthetic in North America? I know GRP 3 is the minimum standard but does that constitute it must be 100% of GRP 3 or above? Further, what is the dividing line in the refining process to move up from GRP 2?

The reason I ask is when I look at the PDS for Castrol GTX Magnatec 5w20 that's marketed as a full synthetic their properties look very similar to that of a GRP 2 conventional (specifically the SG). Is Castrol moving the goal posts again like they did a number of years ago with the dispute with Mobil? Are they using a higher percentage of a high molecular weight base oil like PAO40?

Very curious indeed. Your thoughts?

 

[A_Harman]

You can't look at a single value on a spec sheet, such as SG, and make any conclusions about an oil's base stock group.
Your best chance to find out such information is to look at the MSDS. Typically, Castrol's data sheets aren't very informative.
VI above 120, severe hydrocracking, and possibly isomerization is what separates group 3 from group 2.
I have been thinking that Magnatec contains some esters that add polarity to the oil to provide "clinginess" to engine parts.

 

[Tom NJ]

The word "synthetic" is a marketing term. There are no formal definitions or policing of the term. It is industry practice to use the term for oils base entirely on Group IIIs, Group IVs, and some Group Vs, however, not all adhere to that practice. The only difference between a Group II (mineral) and a Group III (synthetic) base oil is one VI point, a meaningless distinction. Furthermore, there are no tests that can distinguish between a Group II and a Group III, or determine the percent of Group III, in a finished oil.

About the only conclusion you can draw from a synthetic label is that the oil probably has a more stable base oil blend than one not labeled synthetic. But unless you are extending drains or running unusually hot engines, this is not that important compared to the additives. Industry and OEM approvals are your best guide to oil performance.

Tom NJ

 

[kschachn]

Originally Posted By: Tom NJ
The word "synthetic" is a marketing term. There are no formal definitions or policing of the term. It is industry practice to use the term for oils base entirely on Group IIIs, Group IVs, and some Group Vs, however, not all adhere to that practice. The only difference between a Group II (mineral) and a Group III (synthetic) base oil is one VI point, a meaningless distinction. Furthermore, there are no tests that can distinguish between a Group II and a Group III, or determine the percent of Group III, in a finished oil.

About the only conclusion you can draw from a synthetic label is that the oil probably has a more stable base oil blend than one not labeled synthetic. But unless you are extending drains or running unusually hot engines, this is not that important compared to the additives. Industry and OEM approvals are your best guide to oil performance.


Thank you. The constant emphasis on base stock composition is so misguided.

 

[ndfergy]

Thanks all, specifically TomNj.

WOW, that's quite the revelation. I'm now even more dubious of synthetic oils. I'll stick to my cheap group 2 conventional.

 

[y_p_w]

I'm kind of at a point where I think the term "synthetic" should be scrapped because it basically doesn't tell the consumer anything terribly useful. Performance standards should really be the goal.

Still - I do remember way back when "synthetic motor oil" was universally representative of a group IV/V blend, but the label would always have a footnote for "synthetic" that would say "exclusive of additive carrier oil". Apparently most additive packages came in a group I base oil, and that would mean a sizable amount of the finished product was group I. I think at this point there are additives that are suspended in different types of base oils.

 

[ndfergy]

Agreed, something along the lines of ACEA. Fat chance that happening anytime soon. Clarity would be an anathema where obfuscation is a sales bonanza akin to spending $200 on a HDMI cable. Not saying that synthetics aren't better, but within the GF-5 spec one wonders how big or small that degree really is.

 

[Tom NJ]

Up until 1996, the term "synthetic" was clearly defined in the SAE J357 Standard, paraphrased as follows:

Chemical compounds...produced by chemical synthesis...and manufactured by organic reactions...from relatively pure organic starting materials.

This definition included PAOs and esters, the synthetic base oils in use at the time, but clearly excluded any mineral base oils.

With the arrival of Group IIIs, this SAE definition was challenged and the SAE decided to step back from the controversy and just dropped the definition altogether in the 1996 edition of the Standard. With no official party defining the term, the word synthetic was relegated to the marketplace.

In 1998 the National Advertising Division of the Better Business Bureau ruled against Mobil's challenge to Castrol, who was using the word for a Group III+ based oil. While this ruling only applied to the specific Castrol formulation using a Group III+ base oil, the industry decided it was safe to now call all Group III based oils synthetic. This narrowed the distinction to a single VI point and stripped the word of any real meaning.

Naturally the manufacturers of PAOs and esters were not happy with this change since they invested in the word synthetic for decades, only to have its meaning blurred while every competitor jumped in with their own Group III "synthetic" oils, making the same claims as PAOs and esters and riding their reputation for increased profit.

That said, consumers have benefited from this change over the past 20 years as the wide availability of Group III oils allowed and encouraged engine manufacturers to raise the bar on oil quality with higher performance specifications. Overall, the quality of today's oils are far superior to those of the past and at much lower prices than the old "synthetics" of the past.

Tom NJ

 

[y_p_w]

Originally Posted By: Tom NJ
That said, consumers have benefited from this change over the past 20 years as the wide availability of Group III oils allowed and encouraged engine manufacturers to raise the bar on oil quality with higher performance specifications. Overall, the quality of today's oils are far superior to those of the past and at much lower prices than the old "synthetics" of the past.

I seem to recall that one clear superiority of a PAO/ester base oil was in low-temperature performance. I'm not sure that's all that critical for me, because even a winter trip to the Sierra Nevada is adequately served by a cheap 5W-20/30 oil.

 

[SR5]

Thanks Tom
Well stated.

 

[ndfergy]

Thanks for the further edification. Your knowledge in this field, including other members, is superior to mine.

 

[Garak]

Originally Posted By: kschachn
Thank you. The constant emphasis on base stock composition is so misguided.

I can be a base stock snob at times, but that's mainly because I'm still annoyed with how things changed years ago. Of course, yes, following approvals is probably the safest bet to getting value for your money. If a 5w-30 from an unknown source is marketed as synthetic, it had better have A5/B5 or a legitimate dexos1 license to justify the price premium over a conventional.

 

[Toaster_Jer]

Thanks everyone, especially Tom NJ. No one knows everything, I try to be open minded. Things learned, easily become outdated.