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Comparative Motor Oil Testing

API Motor Oil Testing:

AMSOIL Synthetic 10W-30 Motor Oil (ATM) and 10 competing conventional and synthetic 10W-30 motor oils were subjected to a series of API motor oil tests. The competing oils included petroleum-based Castrol GTX Drive Hard, Mobil Drive Clean, Pennzoil with Purebase, Quaker State Peak Performance and Valvoline, as well as synthetic-based Valvoline Synpower, Quaker State, Castrol Syntec, Pennzoil and Mobil 1 SuperSyn Multi-Vehicle.

AMSOIL competes head to head with Castrol, Valvoline, Mobil, Pennzoil, Quaker State

Seven API tests were run on the motor oils. The Thin-Film Oxygen Uptake Test (TFOUT) measures the oxidation stability of engine oils. The High Temperature/High Shear Test (HTHS) measures a lubricant's viscosity under severe operating conditions. The NOACK Volatility Test measures the evaporation loss of oils in high temperature service. Pour Point indicates the lowest temperature at which a fluid will flow. Total Base Number (TBN) is the measurement of a lubricant's reserve alkalinity for combating acids. The Cold Cranking Simulator Test (CCS) measures a lubricant's viscosity at low temperatures and high shear rates. The Four-Ball Wear Test measures a lubricant's wear protection properties. The impressive test results show AMSOIL Synthetic 10W-30 Motor Oil outperformed the competitors in each test.

Thin-Film Oxygen Uptake (ASTM D-4742):

The Thin-Film Oxygen Uptake Test evaluates the oxidation stability of lubricating oils. A mixture of the test oil and chemistries found in gasoline engine operation (oxidized/nitrated fuel, soluble metals and distilled water) are placed in a test vessel, which is pressurized with oxygen and placed in a heated bath. Anti-oxidant breakdown is evident when the oxygen pressure in the vessel rapidly decreases. At this point, the induction time (break point) of the oil is recorded. As shown in the graph, AMSOIL Synthetic 10W-30 Motor Oil had the highest induction time of all the tested oils. In fact, it didn't reach its break point in over 500 minutes of testing.

The superior oxidation stability of AMSOIL Synthetic 10W-30 Motor Oil allows it to effectively resist the formation of engine deposits and sludge, keeping engines running clean and efficient and extending oil life. It also resists thickening, maintaining its superior wear protection and lubricating properties and maximizing fuel efficiency.

Amsoil ASTMD-4742 testing

High Temperature/High Shear (ASTM D-4683):

The High Temperature/High Shear Test measures a lubricant's viscosity under severe high temperature and shear conditions that resemble highly-loaded journal bearings in fired internal combustion engines. In order to prevent bearing wear, it is important for a lubricant to maintain its protective viscosity under severe operating conditions. The minimum High Temperature/High Shear viscosity for a 30 weight oil is 2.9 cP. As shown in the graph, AMSOIL Synthetic 10W-30 Motor Oil surpasses this minimum standard and displayed the highest High Temperature/High Shear viscosity in the group.

The superior viscosity retention of AMSOIL Synthetic 10W-30 Motor Oil in the face of severe temperature and shear conditions allows it to provide continuous, unsurpassed protection for engine bearings, extending equipment life and preventing wear.

Amsoil ASTMD-4683 testing

NOACK Volatility (ASTM D-5800):

The NOACK Volatility Test determines the evaporation loss of lubricants in high temperature service.The more motor oils vaporize, the thicker and heavier they become, contributing to poor circulation, reduced fuel economy and increased oil consumption, wear and emissions. A maximum of 15 percent evaporation loss is allowable to meet API SL and ILSAC GF-3 specifications. As shown in the graph, AMSOIL Synthetic 10W-30 Motor Oil outperformed its nearest competitor by over 30 percent.

The extremely low volatility of AMSOIL Synthetic 10W-30 Motor Oil allows it to maintain its superior protective and performance qualities throughout extended drain intervals, even when faced with severe operating temperatures. In addition, oil consumption and emissions are minimized and fuel efficiency is maximized.

Amsoil ASTM D-5800 testing

Pour Point (ASTM D-97):

The Pour Point Test determines the lowest temperature at which a lubricant will flow when cooled under prescribed conditions. The lower a lubricant's pour point, the better protection it provides in low temperature service. As shown in the graph, AMSOIL Synthetic 10W-30 Motor Oil has the lowest pour point of the tested oils.

The low pour point of AMSOIL Synthetic 10W-30 Motor Oil allows it to maintain its fluidity in extremely low temperatures, reducing drag on moving vehicle parts, providing critical engine components with quick, essential lubrication and easing startup in cold temperatures. Wear is greatly reduced and equipment life is extended.

Amsoil ASTM D-97 testing

Total Base Number (ASTM D-2896):

Total Base Number (TBN) is the measurement of a lubricant's reserve alkalinity, which aids in the control of acids formed during the combustion process. The higher a motor oil's TBN, the more effective it is in suspending wear-causing contaminants and reducing the corrosive effects of acids over an extended period of time. As shown in the graph, AMSOIL Synthetic 10W-30 Motor Oil has the highest TBN of the tested oils.

The high TBN of AMSOIL Synthetic 10W-30 Motor Oil allows it to effectively combat wear-causing contaminants and acids, providing superior protection and performance over extended drain intervals.

Amsoil ASTM D-2896 testing

Cold Crank Simulator (ASTM D-5293):

The Cold Crank Simulator Test determines the apparent viscosity of lubricants at low temperatures and high shear rates. Viscosity of lubricants under these conditions is directly related to engine cranking and startability. The lower a lubricant's cold crank viscosity, the easier an engine will turn over in cold temperatures. 10W motor oils are tested at -25°C and must have a viscosity below 7000 cP to pass. As shown in the graph, AMSOIL Synthetic 10W-30 Motor Oil is well below the maximum requirement, while many of the competing oils barely pass.

The low cold crank viscosity of AMSOIL Synthetic 10W-30 Motor Oil reduces drag on moving engine parts and allows engines to achieve critical cranking speed in extremely frigid temperatures. Engines turn over quickly and dependably in the coldest winter temperatures.

Amsoil ASTM D-5293 testing

Four Ball Wear (ASTM D-4172):

The Four Ball Wear Test determines the wear protection properties of a lubricant. Three metal balls are clamped together and covered with the test lubricant, while a rotating fourth ball is pressed against them in sliding contact. This contact typically produces a wear scar, which is measured and recorded. The smaller the average wear scar, the better the wear protection provided by the lubricant. As shown in the graph, AMSOIL Synthetic 10W-30 Motor Oil produced the smallest wear scar of the tested lubricants.

AMSOIL Synthetic 10W-30 Motor Oil provides unsurpassed protection against engine wear. Equipment life is extended, and repairs, downtime and expenses are reduced.

Amsoil ASTM D-4172 testing

AMSOIL INC. has been the leader in synthetic motor oil formulation since its introduction of the world's first API rated synthetic motor oil in 1972. By specializing exclusively in synthetic lubricant technology, AMSOIL is able to optimize the most advanced chemistries available. The "Genuine Synthetic PAO Formulated" designation displayed on AMSOIL packaging indicates that the oils are formulated with Polyalphaolefin (PAO) synthetic base stocks. This chemistry is the industry's premier base stock technology. Unlike conventional mineral-based chemistries, AMSOIL PAO base stocks contain fully saturated, hydrogenated molecules and are free of wax and other impurities. Combined with an exact balance of premium additives, it delivers superior hot and cold temperature performance, resists oxidation and acid formation and provides long-term wear protection. AMSOIL "Genuine Synthetic PAO Formulated" oils have shattered the parameters of the most rigorous industry testing and set the standard for all other motor oils.

AMSOIL is the undisputed leader in synthetics

Since 1972, AMSOIL Synthetics have proven to be the BEST. AMSOIL also engineers and manufactures Super Duty Oil filters which have a 12,500 mile service life as well as specialized filtration systems for commercial and fleet applications in cars and light, medium and heavy trucks which can filter particles down to less than one micron (a standard full flow oil filter can only filter to 20-25 microns with any degree of efficiency) making oil changes virtually unnecessary and virtually eliminating engine wear. These filters have been proven by millions of miles of over-the road trucks, construction equipment and fleet service.

  • AMSOIL saves you time and money.

  • The only 25,000 mile/one- year and 35,000/one- year motor oil in the world.

  • Exceeds the most stringent performance specifications of all major U.S. and foreign automotive and truck manufacturers.

  • Provides up to two-times the wear protection of other motor oils.

  • Increases the life of your vehicle.

  • Improves performance, fuel economy and efficiency.

  • Diesel oil and filtration products designed to deliver 1,000,000 miles for over-the-road trucks before engine overhaul.

  • Used by many national racing teams, fleets, police departments, construction firms and trucking companies.


High Performance Synthetics is comprised of a group of highly skilled team of Engineers and Lubrication and Filtration Specialists. You too, can join our group when you become an AMSOIL Dealer and take advantage of all that we offer as you use products in your own vehicles or begin your own AMSOIL business. You won't find a more knowledgeable and skilled group of Dealers anywhere which is very important when you need support as you build your business.

In addition, as a Dealer in our group you will receive exclusive unlimited product, technical and business support from the only group of Truck and Automotive Engineers and Lubrication Specialists on the net.

We do not only run our business on the internet. We also have numerous commercial, industrial, trucking, excavating, construction, logging, police, racing and many more accounts that we support and service on a regular basis. We have several fully stocked warehouses and fully equipped shop facilities. This provides us with excellent knowledge of the products, equipment and the business and the ability to respond immediately to any of your needs. We will use this knowledge and experience to help you get started so you too can achieve your goals.

We possess the skills, desire and knowledge to answer questions, solve problems, improve efficiency, reduce downtime, maintenance costs and increase the durability and life of all of your vehicles.

Read what our satisfied customers have to say about us. Read through our website. Contact us with any questions. If you decide to become an AMSOIL Dealer you will be joining, in our opinion, the most skilled AMSOIL group there is. We will help you get started and provide you with the tools and information in order to be successful in this business or with technical and product assistance to use AMSOIL products in your own vehicles.

We offer several options to receive information on AMSOIL. We welcome the opportunity to work with your personally as your servicing AMSOIL Dealer. Our AMSOIL Dealer Group is led by a Truck/Automotive Engineer and Lubrication Specialist with over 18 years experience. This exceptional benefit is unavailable elsewhere.

Please, contact us (CLICK HERE for contact info) and we will send you an exclusive comprehensive package of product, technical and business information. If you are serious about AMSOIL products and the business opportunity this is the best option. You will receive extensive technical and business support from both myself and my Direct Jobber, a Detroit, Michigan Truck/Automotive Engineer and Lubrication Specialist with over 19 years experience. We look forward to helping you learn about AMSOIL.

Or for a smaller, very general information package (which includes a catalog and Dealer application) you can request information via any of the links below.

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AMSOIL is America's Oil.


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