Does anyone know more about which oils are really synthetic? I know that some of the "synthetic blend" oils are sometimes not very synthetic, just enough in there to be called "synthetic"

Supposedly 'full synthetic', Castrol Syntec:
"Castrol switched syntec (except German made 0W30 "GC") from a PAO base oil to a highly refined dino, so it is basically fake (they only market it as synthetic in North America, in the rest of the world they call it semi-synthetic)."

more marketing abuse of words, like "digital" "organic", etc...!

According to the Mobil 1 website in the FAQ section, Mobil 1 is fully synthetic.

From whence cometh thy quote?
I haven't heard anything against Syntec before.

_________________
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"A mechanic is Somebody."
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I wouldn't expect a "synthetic blend" oil to be completely synthetic. The blend in the title refers to synthetic blended with conventional dino.

Mobil 1, Redline and Amsoil are common/popular synthetics.

Valvoline, Castrol, etc, sell blended versions of their synths, cheaper alternatives I guess. However, if they advertise full synth, they'd have to be or else be in line for lawsuits and the like. I've used Syntec (not blend)before and been very happy with it.

_________________
O==\=/==O

"A mechanic is Somebody."
- Jim Preston

mobile 1, amsoil, redline, and royal purple are the only true PAO synthetics anymore. All the others are now using super-refined, modified dino oils now.

Someone set a precedent & won a case in court; so, now everyone can use the cheaper oil base (group III?), call it "sythetic oil" and get away with it as long as it's refined to this higher level...

Lubes'N'Greases, Jul. 2001. 2 pages.
"... a 1999 ruling by the National Advertising Division of the Better Business Bureaus broadened the definition of synthetic lubricants to include Group III base stocks. With Group III granted the right to wear the Œsynthetic label -­ and a cost differential of $1.50 to $2.00 a gallon in favor of Group III ­ most large lubricant producers moved quickly to replace PAO with Group III in their synthetic PCMO formulations."

taken from Chevron Texaco Lubricants - Base Oils

it turns out I was wrong about Mobile1:

In the late 1990s, Castrol started selling an oil made from Group III base oil and called it SynTec Full Synthetic. Mobil sued Castrol, asserting that this oil was not synthetic, but simply a highly refined petroleum oil, and therefore it was false advertising to call it synthetic. In 1999, Mobil lost their lawsuit. It was decided that the word "synthetic" was a marketing term and referred to properties, not to production methods or ingredients. Castrol continues to make SynTec out of Group III base oils, that is highly purified mineral oil with most all of the cockroach bits removed.

Shortly after Mobil lost their lawsuit, most oil companies started reformulating their synthetic oils to use Group III base stocks instead of PAOs or diester stocks as their primary component. Most of the "synthetic oil" you can buy today is actually mostly made of this highly-distilled and purified dino-juice called Group III oil. Group III base oils cost about half as much as the synthetics. By using a blend of mostly Group III oils and a smaller amount of "true" synthetics, the oil companies can produce a product that has nearly the same properties as the "true" synthetics, and nearly the same cost as the Group III oil. In fact, Mobil-1 is now primarily made from Group III unconventional base oils, exactly the stuff Mobil was claiming was not really synthetic.

taken from All About Oils.

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yeah, that's what i was talking about, the modified dino's being sold as "fully synthetic" !!!

i understand the blends being a mix of the two, but even these have very little synthetic in them, from what i have been reading...

i'm going to go with Mobil 1 next time around...

As Charlie Brown says; "Good Grief!"
You really can't trust anybody, can you?
Lawyers...

_________________
O==\=/==O

"A mechanic is Somebody."
- Jim Preston

Taken directly from the faq at mobile1.com:

Is Mobil 1 with SuperSynâ„¢ a fully synthetic motor oil?
Yes, it is. To meet the demanding requirements of today's specifications (and our customers' expectations), Mobil 1 with SuperSynâ„¢ uses high-performance fluids, including polyalphaolefins (PAOs), along with a proprietary system of additives. Each Mobil 1 with SuperSynâ„¢ viscosity grade uses a unique combination of synthetic fluids and selected additives in order to tailor the viscosity grade to its specific application.


Hmm, interesting.

Synthetics come in different formulations. PAO and diesters. The difference is in the base stock.

Mitch