Machinery Lubrication - 'GrpIII syn is mktng term'

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Site Donor 2023
Apr 4, 2012
Kendall, FL

Types and Terminology

There are two American Petroleum Institute (API) base oil categories that include synthetics. The first is API Group IV. The only synthetic base oil included in this group is polyalphaolefin or PAO. PAOs are made by polymerizing an alpha-olefin molecule like ethylene. In an alpha-olefin molecule, there is a carbon-carbon double bond with hydrogen branching off.

The second category is API Group V. These are non- PAO synthetic bases. Examples include diesters, polyolesters, alkylated benzenes, phosphate esters, etc. Basically, if it is a synthetic and it is not a PAO, it is a Group V.

Some confusion has arisen recently regarding the use of the word “synthetic.” Several petrochemical companies have developed processes involving catalytic conversion of crude oil base stock under high pressures and temperatures in the presence of hydrogen to form very high-quality mineral lubricants. These oils, which are known as API Group III, are so highly refined that their properties almost match that of the Group IV synthetics. They are so close in fact that the U.S. court system sided with a manufacturer of these Group III “synthetics” when a lawsuit was brought up for false advertising. Even though these Group III base oils are derived from crude oil, they can now legally, from a marketing standpoint, call them synthetic.
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dude this is so bitog 2004, even if noria published that a mere 3 years ago.

what do they say about oils made from natural gas that are group III?
Uhhh boy, sorry to re-re-post. Tried to delete, but too late.
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Call it what you want, todays synthetics, and thats what I will call them, are high quality and are superior to conventional. No need for top tier synthetics, except in some high stress high performance engines.
Originally Posted By: Rand
dude this is so bitog 2004

This means we are in the bitog future.
Originally Posted By: Garak
It's still a nice read.
But the wording of this perpetuates the ongoing myth that Group V = synthetic. Group V is not a synthetic category. It is a wide-ranging category that includes some synthetics (eg esters, polyglycols, PIB, even silicones) but also includes some minerals (low- and medium-VI minerals, naphthenics etc) and also vegetable oils (eg castor oil).

And the API do not apply any descriptors to these groups, so all are made up by "the industry". It is a marketing term as much for Group IV as it is for Group III.
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