Just curios beause my friend said all base stocks are petroleum but isn't amsoil 100% synthetic base stock unlike pennzoil and Mobil who have highly refined petroleum
can anyone explain base stocks to me?
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Don't fall for the group III base stock trap that Mobil 1, Castrol, and Pennzoil (although, Pennzoil openly admits they use group III, unlike Mobil and Castrol).
Many people see the word "Synthetic" on a bottle of oil and assume it's 100% synthetic. This is not the case. Base stocks fall into four major categories called groups.
Group II - Petroleum oil, commonly called conventional or dino oils
Group III - hydrocracked, or heavily refined pertroleum, has impurities
Group IV - PAO, man made synthetic, no impurities
Group V - diesters, some polarized, allows engine oil to stick like a magnet to metal
First, let's talk about the difference between group III and IV base stocks using a water analogy to understand it in simple terms.
Pump water from a lake, river, or stream into a plant. Purify it, remove minerals, and make it look clear. You have "group III" water.
Take Hydrogen and Oxygen in the purest form, chemically bond them together to make "group IV" water. With no impurities to remove you have more consistent results and hence....True synthetic!
Group III - Petroleum oil that is pumped out of the ground and refined to be classified as a synthetic base stock, although a lot of experts disagree with this. A few oil manufacturers mostly use group III stocks, but still call it a synthetic...they consider the major changes in the refining process to be "synthesizing" oil. You should also note these oils should not say "full" synthetic on the bottle, even though they do. The latest refining, and best of these stocks, are called group III+. These stocks seem to be the best at keeping in-solubles in suspension within the oil to carry it to the filter. Group III+ in the GTL (gas to liquid) category are the closest refined base stocks to rival group IV PAO performance, however....they do not match it in all tests. I'm still waiting for a third party testing facility to see if group III+ base stocks do have sub 6% NOACK.
Group IV - We call them PAO (Poly-Alpha-Olefin). Like the water analogy they are true synthetic, have better cold pour properties, and better resistant to high heat "torture" situations. These base stocks give longer drain intervals.
The rest of a lubricant's formulation is dependent on the additive package.
Want to learn about engine lubricants? The Motor Oil Bible is a 170+ page .pdf file that will keep you busy for a long time, yet very informative.
Many people see the word "Synthetic" on a bottle of oil and assume it's 100% synthetic. This is not the case. Base stocks fall into four major categories called groups.
Group II - Petroleum oil, commonly called conventional or dino oils
Group III - hydrocracked, or heavily refined pertroleum, has impurities
Group IV - PAO, man made synthetic, no impurities
Group V - diesters, some polarized, allows engine oil to stick like a magnet to metal
First, let's talk about the difference between group III and IV base stocks using a water analogy to understand it in simple terms.
Pump water from a lake, river, or stream into a plant. Purify it, remove minerals, and make it look clear. You have "group III" water.
Take Hydrogen and Oxygen in the purest form, chemically bond them together to make "group IV" water. With no impurities to remove you have more consistent results and hence....True synthetic!
Group III - Petroleum oil that is pumped out of the ground and refined to be classified as a synthetic base stock, although a lot of experts disagree with this. A few oil manufacturers mostly use group III stocks, but still call it a synthetic...they consider the major changes in the refining process to be "synthesizing" oil. You should also note these oils should not say "full" synthetic on the bottle, even though they do. The latest refining, and best of these stocks, are called group III+. These stocks seem to be the best at keeping in-solubles in suspension within the oil to carry it to the filter. Group III+ in the GTL (gas to liquid) category are the closest refined base stocks to rival group IV PAO performance, however....they do not match it in all tests. I'm still waiting for a third party testing facility to see if group III+ base stocks do have sub 6% NOACK.
Group IV - We call them PAO (Poly-Alpha-Olefin). Like the water analogy they are true synthetic, have better cold pour properties, and better resistant to high heat "torture" situations. These base stocks give longer drain intervals.
The rest of a lubricant's formulation is dependent on the additive package.
Want to learn about engine lubricants? The Motor Oil Bible is a 170+ page .pdf file that will keep you busy for a long time, yet very informative.
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Thanks unleashed.
Excellent write up Troy! Thanks for that!
Troy has hit it out of the park with that explanation. And bringing up mobil was good too. They are scamming their loyal customers with an average performing product but charging an above average price. I'm glad there are members like beast that will inform the sometimes brand loyal public. If you want a real,true synthetic(group 4/5) you gotta look at red line,royal purple,amsoils sso line among other Amsoil lines,motul makes a few ester based products.
If you are going to pay the synthetic price make sure it's actually synthetic and doesn't say performs like a synthetic. Remember,in north America the term synthetic is a marketing term and doesn't apply to what's in the bottle.
The Europeans don't allow that type of marketing so if your curious look up the same oil you're interested here and see how it's labelled there. They will not allow a group 3 to be called synthetic. Here because of the castrol mobil debacle group 3 oils can be labelled syn or even fully synthetic but aren't. In fact if it says fully synthetic I guarantee it's a group 3 basestock. The real synthetics don't advertise with the word full.
If you are going to pay the synthetic price make sure it's actually synthetic and doesn't say performs like a synthetic. Remember,in north America the term synthetic is a marketing term and doesn't apply to what's in the bottle.
The Europeans don't allow that type of marketing so if your curious look up the same oil you're interested here and see how it's labelled there. They will not allow a group 3 to be called synthetic. Here because of the castrol mobil debacle group 3 oils can be labelled syn or even fully synthetic but aren't. In fact if it says fully synthetic I guarantee it's a group 3 basestock. The real synthetics don't advertise with the word full.
Thanks SR,
I take great pride informing the masses what they are actually buying in a bottle of oil. I wish the US would eliminate the term "synthetic" for use on hydrocracked petroleum. This alone would solve the issue of charging a premium price for an inferior product.
I take great pride informing the masses what they are actually buying in a bottle of oil. I wish the US would eliminate the term "synthetic" for use on hydrocracked petroleum. This alone would solve the issue of charging a premium price for an inferior product.
damn! good to know. thank you
Just to play devil's advocate a bit. While Mobil 1 may not be in the same category as Royal Purple or Amsoil, neither is the price. It is priced between the dino oils and the true synthetics, which is where it would seem to belong.
Wal Mart's buying power has changed the way Mobil 1 is priced in the 5 quart jug. Only Wal Mart has that.
Thank you for the link to the oil bible, that will provide some good reading later.
Who is using the type V base stock? If it is expensive as I expect it to be the usage is probably aviation.
For our street driven engines is there any reason to run a group V, other than bragging rights.
I have been using Mobil 1 in my two, lower performance vehicles since new.
1992 ford Explorer and 2002 Toyota Corolla. Neither of which ever gets revved very high. In the 2003 Cobra I am using Amsoil currently. And it does see 6500 rpm pretty regularly.
For our street driven engines is there any reason to run a group V, other than bragging rights.
I have been using Mobil 1 in my two, lower performance vehicles since new.
1992 ford Explorer and 2002 Toyota Corolla. Neither of which ever gets revved very high. In the 2003 Cobra I am using Amsoil currently. And it does see 6500 rpm pretty regularly.
how did mobil 1's "loyal" customers become that way? i remember way back when (early 90's lol) before all the lawsuits etc, that it used to be actually a full synthetic product, is that correct?
in other words, was mobil 1 "synthetic" originally a group IV oil?
Costco runs Mobil 1 on coupon pretty much once a month for $26.99 for 6qts -limit 3.
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