AMSOIL vs Mobil 1

In a head to head test of AMSOIL vs Mobil 1 who comes out on top?

As you already know this is a very touchy subject.  There are a few topics you should never bring up at a family holiday party... religion, politics, and what motor oil you should use.

If we are truly going to use logic instead of emotion to select between AMSOIL and Mobil 1 then we need some cold hard data from real bench marked testing.

As a degreed and licensed mechanical engineer I have developed a real appreciation for industry standards and codes.  

And for oil evaluation and testing there is nothing more important than third party laboratory bench testing conducted in accordance the American Society of Testing and Materials (ASTM).  We will use ASTM standard tests to make a comparison of AMSOIL vs Mobil 1.

Here are the test results along with some simple explanations of the significance of the results.


Four Ball Wear Test - Mobil 1 Dead Last...

The "four ball wear test" is a great way to separate the men from the boys. 

This is the test where the lab will press and spin a metal ball down into three other balls arranged as a base in a triangle pattern.

The little pyramid of balls is fully submerged in a bath of the oil being tested.  The better the oil protects then the less damage that happens. 

The smaller the wear scar the better...

AMSOIL vs Mobil 1 Wear Scar Test

As you can see the AMSOIL signature series is all the way to the left in first place with the smallest wear scar where Mobil 1 came in dead last ranking 10th place out of 10. 

AMSOIL vs Mobil 1 in Cold Cranking Viscosity Test

Most of your engine wear occurs right when you start your vehicle.  You need to get your oil flowing instantly to minimize wear. 

As you can imagine the thicker your oil is when it is cold the longer it takes for your oil pump to get the oil up through your engine.

The lower the number the better for this test.

AMSOIL vs Mobil 1 Cold Crank Test

As you can see Mobil 1 takes 4th place in the cold crank viscosity test where AMSOIL placed first. 

One of the great benefits of using synthetic oils is supposed to be the low temperature performance so you would expect to see synthetic oils perform very well on this test yet there are some surprising results (lets not talk about Royal Purple and Red Line here... ouch).

NOACK Volatility Test

The NOACK test demonstrated how much an oil evaporates under high temperature service.

If oil evaporates inside your engine it will burn off in the cylinders or through the positive crankcase ventilation system.  This will show up as oil consumption.

When your oil evaporates the oil that is left has different properties and will not protect your engine as well.

The lower the number the better.

AMSOIL vs Mobil 1 Volatility Test

Thermo-Oxidation Engine Oil Simulation Test or TEOST Test

Engine oils form deposits when the are burned off under high heat.  This happens on your fuel injectors, on turbos, and other high temperature areas.

Small deposits on fuel injectors reduce combustion efficiency by altering the injectors spray pattern.  It is surprising how much this will effects your engine power.

The bottom line is you want an oil that does not burn off and when it does it leaves very little deposit. 

In the test results below the lower number the better.

Total Base Number Test

Acid corrosion inside your engine would quickly destroy important clearances and reduce performance if it were not for the reserve alkalinity in your motor oil. 

TBN is a measure of how well an oil will control the acids formed inside your engine.

The higher the TBN number the better.

AMSOIL vs Mobil 1 TBN Test

You can see who takes first in an AMSOIL vs Mobil 1 TBN comparison.  I would have thought with the name Mobil 1 Extended Performance that Mobil would have at least tried to beat out Castrol.

AMSOIL vs Mobil 1 - Which Oil Protects Best and Saves You Money?

AMSOIL signature series synthetic motor oil is recommended for 25,000 miles or one year of service under normal service.

Out of all the oils tested AMSOIL is the only oil that can be changed just once per year where all the other oils would require an oil change a little more than twice per year based on an annual average mileage of 11,318.


As you can see in a comparison of AMSOIL vs Mobil 1 that AMSOIL stands out front. 

You can have confidence in these results because the test were conducted by a third party independent lab.  Samples were taken in random order and were coded to eliminate bias.  The lab did not know which oil was from which manufacturer.

How to get a good discount when you buy AMSOIL

If you like what you see here and you are wondering where can I buy AMSOIL or how to order AMSOIL.  Follow those links for some information on taking the next steps to better engine protection and increased performance.

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