Maybe "synthetic" isn't a good term...

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Group III is "good enough" to be as good as Group IV/V in MOST applications, but it's not as good in extreme heat or cold. That's why Grp. III is NOT "synthetic" in Germany, they require the (big $) real thing.
 
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But it seems all that matters is if the finished product performs as well as a Group IV or V, then it is by default synthetic.
How something performs should not enter into synthetic or no

Synthetic is a definitely material , if processed water can be made to perform like oil it’s still not a “synthetic oil”

The two have nothing to do with one another
 
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Good point. I'd even stretch to compare it to the definitions of metal and plastic. In many applications plastic material such as glass fibre-reinforced PA is more than sufficient (intake, oil pan), but it still isn't called 'steel' since it isn't made of iron.
 
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Many words have multiple definitions and meanings, be they dictionary, technical, legal, religious, etc., and meanings often change by region as well. All are valid in some context. Sometimes definitions change as common use trumps other more formal definitions. Synthesis has a technical definition in chemistry, but its common use definition with respect to motor oils has changed. Whether we agree or disagree is irrelevant as we do not have the power or influence to change this fact. Like complaining about the weather, no sense letting things beyond your control to get under your skin.
 
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Many words have multiple definitions and meanings, be they dictionary, technical, legal, religious, etc., and meanings often change by region as well. All are valid in some context. Sometimes definitions change as common use trumps other mor




Tom NJ, I appreciate your insights put forth in this discussion. I feel like a kindergartener trying to communicate with and understand those who hold doctorate degrees. Typically you can break through to this pre-schooler. 👍
In 1999 the BBB's NAD, in a non-binding non-legal decision related to advertising standards, decided that C
Today about the only conclusion you can draw from a synthetic label is that the oil most likely has a more stable base oil blend than one not labeled synthetic, assuming the marketer is ethical. A more stable base oil is only part of an oil's performance characteristics as the additives dominate in many performance attributes. If you really want to define an oil's performance, look to the industry and OEM approvals it has. These take into account both the base oil and the additives, and at least they are defined and regulated. The term "synthetic" is not.
 
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In aviation we use a term "HTS" or High Thermal Stability. All of our turbine oils are synthetics. We use the trouble-free (spec MIL-PRF-23699F) Eastman 2380 oil, although it's not the best oil and it is not an HTS oil. The reason I bring all of this up is simply this, the MIL-PRF-23699F specification for STD and HTS oils is exactly the same. Even when we drill-40-rows-down into specification data and some completely insane and detailed requirements and allowances.

However, when we get to this one line at the bottom, things change: "ERDCO high temperature bearing rig test (USN)": Demerits (Method 3410, what ever that is), Deposits. The allowable limits are half or less. And therein lies the difference for some engines (example: Turbomeca) , it's coked turbine (hot side) bearings with the use of Eastman 2380 and no problems with HTS Mobil 254.

Our synthetic vs dino discussion really is a Demerits + Deposits subject.

Years ago in our turbocharged engine testing, it became quite clear that coking on turbocharger shafts was a "dino" oil thing and did not occur with synthetics. Today, many oils are much better, but the problem remains. What people don't see is the design changes made to turbochargers to "fix" or cover up the problem.

As always, if you are operating an engine with known hot components or a propensity to build up deposits, why not choose an oil that can tolerate the heat without deposits or oxidation. Performance matters.
 
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