Brothers, I did some research just using the 2 sites and a couple phone calls. I am NOT trying to bash ANY company just open eyes to the truth, and in this economy save a friend some money. Just because I’m in the business with EXXON MOBIL and CONOCO PHILLIPS, doesn’t mean anything – just trying to educate. I am not the kind of guy to stand up for a product I DON’T believe in. But the research is out there. Let’s compare Mobil to Amsoil, and filter through different ways to advertise…

Base Stocks: There are five specific categories of base oils. These categories
define the type of base stock the oil is formulated from. Group
II, II+, III type mineral base oil stocks and I are widely used in
combination with additive packages, performance packages,
ester and/or Group IV Polyalphaolefins in order to formulate semi
synthetic based lubricants. Group III base oils are sometimes
considered as synthetic but they are still classified as highest
top-level mineral base stocks. A Synthetic or Synthesized material
is one that is produced by combining or building individual units
into a unified entry. Synthetic base stocks as described above are
man-made and tailored to have a controlled molecular structure with
predictable properties, unlike mineral base oils, which are complex
mixtures of naturally occurring hydrocarbons.
Mobil site: Synthetic Oils FAQs

Mobil 1 uses high-performance fluids, including polyalphaolefins (PAOs), along with a proprietary system of additives. Each Mobil 1 and Mobil 1 Extended Performance viscosity grade use a unique combination of synthetic fluids and selected additives in order to tailor the viscosity grade to its specific application. The only way to obtain polyalphaelefins is by using a group IV base stock. According to the AMSOIL site, which is true. Also, during a lunch with my rep, he stated that is is ILLEGAL for a company to state that any company use group v as a base. Group v is an additive for the other groups, not a stand alone base stock. So technically all oil company’s most likely use a certain percentage of the group v in their blends, and full synthetics ect. So for a distributor to advertise that they use group iv and v stocks in their synthetics…...well that’s normal. I hope I am not coming off as a jerk about this.

page #2


secondary Amsoil site( I don't think it is thier actual site sorry if i'm wrong): Motor Oil Base Stock Groups

There are five groups of base stocks, with each generally categorized as follows (AMSOIL Synthetic Oil base stock is Polyalphaolefins (PAOs) or group 4, with a small amount of ester (there is the group v additive) to help control seal swell.

Base OilCategory ManufacturingMethod Oil Characteristics
Group I Solvent Freezing. Group I base oils are the least refined of all of the groups. They are usually a mix of different hydrocarbon chains with little or no uniformity. While some automotive oils on the market use Group I stocks, they are generally used in less demanding applications.
Group II Hydroprocessing and Refining. Group II base oils are common in mineral-based motor oils currently available on the market. They have fair to good performance in lubricating properties such as volatility, oxidative stability and flash/fire points. They have only fair performance in areas such as pour point, cold crank viscosity and extreme pressure wear.
Group III Hydroprocessing and Refining. Group III base oils are subjected to the highest level of mineral oil refining of the base oil groups. Although they are not chemically engineered, they offer good performance in a wide range of attributes as well as good molecular uniformity and stability. They are commonly mixed with additives and marketed as synthetic or semi-synthetic products. Group III base oil products have become more common in America during the past decade.
Group IV Chemical Reactions. Group: IV base oils are chemically engineered synthetic base stocks. Polyalphaolefins (PAOs) are a common example of a synthetic base stock. Synthetics, when combined with additives, offer excellent performance over a wide range of lubricating properties. They have very stable chemical compositions and highly uniform molecular chains. Group IV base oils are becoming more common in synthetic and synthetic-blend products for automotive and industrial applications.
Group V As Indicated Group V base oils are used primarily in the creation of oil additives. Esters and polyolesters are both common Group V base oils used in the formulation of oil additives. Group V oils exhibit a wide variety of properties specific to each individual oil's formulation. Group V base oils are generally not used as base oils themselves, but add beneficial properties to other base oils.
Mobil does infact use group IV base stocks just as Amsoil in their synthetic oils, but they just don’t come out and use it as a marketing ploy…to sound better. To have a full synthetic, you must use the group iv stock. Best thing is they buy it from MOBIL!!!!! Which took some digging to find out… So the true synthetic make up for a group IV is from Mobil with the purchaser’s additive package. Exxon Mobil’s base stock is the most commonly used amongst oil companies today.

Page #3

There are lots of good oils out there on the market, but a consumer shouldn’t have to think that the more they spend, the better a product they get.


Here is some testing done that means the most to a turbo diesel nut. 1500 degrees!

Mobil 1 Heat Protection

I know that in these times, $$$ matters!

Thank You!! And keep the info coming! (Please!) We all need to learn a whole lot about oils! The top engineers in these companies have several doctorates for a reason. This is complicated stuff!
Thank you for all the effort you are putting into this. Don't worry: it is easy to tell when a salesman is being a salesman or when he is being helpful as you are being here!
Your friend,
Dan

good info, I've been using amsoil for a while and have had good luck, so they use Mobile base stock, I'm ok with that, I've put probably 100 gallons of Mobil 1 sythetic 5-30w through some gmc's I used to maintain with great luck.

unless I am missing something big, it seems the only difference is the additive package, and amsoils additive package is very application specific (according to their website anyway) does Mobile have application specific oils? and if so where do I find them?

I like saving money, but when it comes to oils I'd rather pay more for a superior product, whatever it may be, if you say Mobil has products that are comparable or superior I am definitely listening.