There are two basic kinds of motor oil = dino and synthetic.
"Dino" is short for dinosaur. So in other words, dino oil is any oil made from crude oil or petroleum. It's also called "mineral" oil. The 'dino" name is based on the fact that crude oil is the leftovers from dinosaurs and other plants and animals that lived and died millions of years ago.
"Synthetic" oil is usually made from vegetable oil. Ignore the AMSoil salesman - he doesn't know what he's talking about. There are numerous brands of synthetic motor oil that are just as good as AMSoil, and they are all made from vegetable oil, so they are all synthetic. There are also some brands of oil that are semi-synthetic, i.e., a mix of dino oil and synthetic oil. And there is some controversy on the definition of "synthetic".
You can probably look it up in French. Start with the following terms:
Polyalphaolefin (PAO) = American Petroleum Institute
(API) Group IV base oil
Synthetic esters, etc = API Group V base oils (non-PAO synthetics, including diesters, polyolesters, alklylated napthlenes, alkyklated benzenes, etc.)
Then there is the API Group III base oils that cause the controversy. They began life as petroleum, but have been refined to be a synthetic oil instead of a normal mineral oil.
Originally Posted by Wikipedia
Groups I and II are commonly referred to as mineral oils
(or dino oils), group III is typically referred to as synthetic (except in Germany and Japan, where they must not be called synthetic) and group IV is a synthetic oil
. Group V base oils are so diverse that there is no catch-all description.
The above quote was found in: Motor oil - Wikipedia, the free encyclopedia
. There is probably a similar article in the French edition.