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Amsoil vs Mobil 1: Difference & Which Is Better?

The buzz around Amsoil vs Mobil 1 oils is no secret. And differing opinions about which of the two oil brands provides better overall protection have been a long-standing contestation. Responses from vehicle owners are usually dependent on the type of car or mode of transport they own. Mobil 1 is more favored within racing circles, and Amsoil is more popular with people living in colder regions.

So, what is the difference between Amsoil and Mobil 1, and which is better? Given similar viscosity grades, the differences between Amsoil vs Mobil 1 brands are almost negligible. Riders choose Mobil 1 for its proven performance under extreme conditions. However, the majority of consumers regard Amsoil as the best premium and overall synthetic oil.

In reality, there is no cookie-cutter way to establish a more superior brand between these two giants. Determining the better-performing oil will ultimately be up to you, the consumer. That said, read on and let this guide help you make that decision.

Car Motor Oil Pouring into Engine

The Advent of Synthetic Oils

If there was anything good from WWII, it was synthetic oil. Germans originally pioneered this technology during the 1940s amid all the grim and chaos. And when the war was over, this innovation made its way into aviation in the ‘60s, where synthetic esters became popular and were used in turbine engines. It was at this point that current big oil companies saw the potential for synthetic oils.

Amsoil and Mobil, who were involved in synthetic oil production, began working on developing a variant that was better suited for automotive applications. Mobil launched the synthetic oil industry with Synthetic Mobil Grease 28 (used by the air force) and the New Concept Engine Oil Team created in 1971. However, Amsoil beat Mobil to it by formulating the first API-certified fully synthetic SAE 10W-40 motor oil, which hit the shelves in 1972.

Determining Which Is Better – Amsoil vs Mobil 1

Determining the best oil for your vehicle is a matter of personal preference and intended vehicle application. These factors have more weight than the actual attributes or benefits of any given motor oil. Consider the following aspects when choosing between Amsoil and Mobil 1 motor oil variants:

Oil Blend

In a previous article, we covered the different types of oil blends, namely:

  • Premium conventional oil – mineral oil type designed for daily commuters and simple engines
  • Synthetic blend oil – blend mixed with organic oil and best known for its oxidation-resistant properties, engine protection, and temperature stability; ideal for hauling and off-roading.
  • Full synthetic oil – blend with fewer impurities and enhanced extreme-temperature performance; compatible specifically with high-tech engines.
  • High-mileage oil – oils that cater to older vehicles with six-figure miles under their belt; contains anti-wear additives as well as seal conditioners that help mitigate aging-seal problems and cover piston-to-cylinder clearances better.

Both Amsoil and Mobil 1 have a wide array of oil types, most of which are currently full synthetic and synthetic blends. While each type contains its share of special additives and conditioners, you must check the compatibility of these ingredients with your vehicle. As high-quality as these oil blends are, using the wrong type for your wheeler may lead to catastrophic results. At the very least, it could speed up engine wear and tear.

Change Interval

In the past, the schedule for oil changes was solely determined by vehicle type. It still is (OEM recommendations in the owner’s manual should still be adhered to). But with the advent of synthetic oil variants, extended change intervals became possible. From every 3,000 miles, most car manufacturers now recommend oil changes to happen every 5,000 to 7,500 miles. Certain vehicles (and specific synthetic oil types) permit prolonged, even annual oil changes.

While full synthetic oils and synthetic blends have a much longer shelf life, going for these oil types with the aim of extending change intervals may not always be the best route to take. In addition to manufacturer recommendations, going for either Amsoil or Mobil 1 motor oils should be based on driving habits. To put it simply, wheelers subject to hard-driving versus those used as a daily commuter would require oil blends and service schedules. Consequently, specific vehicles tend to perform better with either one of the two oil brands in focus.

Engine Upgrades

Car Engine Machine Part

Among the things riders need to understand is how engine mods affect their selection process when it comes to motor oils. This is incredibly vital as there is a world of difference between the needs of a stock engine and a modded, high-performance power mill. Adding horsepower increases not only RPMs but also stress on the engine and its different parts – the crank, cam, pistons, and bearings. Plus, an increase in shearing forces brought about by upgrades tear apart the molecules of additives meant to extend the base oil’s viscosity range. Hence, an oil variant with more potent viscosity improver and shear-resistant properties – either from Amsoil or Mobil 1 – will work better for your vehicle.

Vehicle Use/Abuse

Alongside its service schedule, the severity and frequency of vehicle usage also play a part in deciding whether Amsoil vs Mobil 1 motor oils would work best with your wheeler. Cars categorized under normal service would typically require oil changes every 12,000 to 25,000 miles (using premium engine oil), whereas those classified under severe service warrant half that mileage or even less for mandatory oil changes. Some examples of severe service include turbo/supercharged engines, fleet vehicles, trucks/SUVs used for frequent towing or in dusty riding conditions, and average cars put through excessive idling and stop-and-go driving.

Fuel/Oil Economy

Specific variants under the Amsoil and Mobil 1 labels reduce oil consumption and make engines more fuel-efficient. Between full synthetic and synthetic blend variants, the former does a better job retaining oil viscosity that helps with engine protection and increases fuel economy. According to blind test results (source: Road Sumo), Amsoil oils have been proven to provide 1.5 to 3.0 more MPG than Mobil 1.

With or without Amsoil vs Mobil 1 independent testing, the information labels found on oil containers should indicate whether or not fuel and oil consumption is optimized. As a general rule, lower-grade oils require less energy to be pumped. However, you should not go against manufacturer recommendations for the sake of fuel cost-effectiveness.


How location influences one’s motor oil of choice is already common knowledge to beginner and experienced riders. Environmental temperature (or where you frequently ride your wheeler, at least) impacts oil viscosity even for multi-grade oils. Winter-grade oils are required for an engine to run more effortlessly in colder areas like Canada or the cooler U.S. states. Conversely, more viscous summer-grade oils perform better and effectively reduce engine wear and tear in hotter climates.

Between the two brands, Amsoil motor oils are thinner and perform more like winter-grade oils, while Mobil 1 variants share the same characteristics as summer-grade oils and have better film strength. Depending on where you live, you may have to choose one over the other. Heck, you may even need to change viscosity grades in-between seasons (or switch oils in the absence of your go-to brand).


More than the brand, the motor oil’s viscosity grade is of greater importance when choosing between Amsoil and Mobil 1 products. In essence, both offer the most common oil grades from 0W20 to 20W-50. Depending on the type of oil blend recommended for your vehicle, some variants may only be available through one of these two brands.

If your required motor oil is available through both, be assured that selecting a specific viscosity grade from either brand will result in similar performance. Should you need a full rundown of different viscosity levels for low and high-temperature motor oils (updated as of April 2, 2013), check out this article.


Finally, consider the cost per quart when choosing between Amsoil and Mobil 1 synthetic oil brands. After all, using synthetic variants is more expensive than conventional oil, and not all oil types offer longer drain intervals. But do not let this detail deter you. Depending on your driving style, choosing synthetic oils for your car can save you money. People who drive an average of 15,000 to 18,000 miles per year can save approximately $150 to $200 per vehicle owned (sans savings on fuel consumption).

Synthetic Oil Testing

Yellow Car Engine Motor Oil

While the above factors are enough to qualify which between Amsoil and Mobil 1 oils is better, some consumers cannot help but look for hard proof to put one brand over the other. This is where oil testing – ranging from the simple to the complex – comes in. Depending on motor oil properties you deem most important, some tests may provide you more meaningful results.

The MPG Test

This test is straightforward and does not require a chemist to be performed. More importantly, it is rig-free. The MPG values your vehicle gets is an exact formula of energy used, made possible by the engine’s efficiency to overcome resistance. A high-quality oil helps internal components encounter less resistance, resulting in greater MPG. The test is best conducted using two different vehicles with similar engines. If this is not doable, make sure to test Mobil 1 oils first and Amsoil oils last. The reason behind this is that Amsoil variants contain protective qualities that may leave residue inside the motor, causing other test results to be skewed.

NOACK Volatility

Although this is classified as a bench test, the NOACK Volatility is not as simple as determining a vehicle’s MPG. It determines the evaporation loss of lubricants in high-temperature conditions and, as such, requires proper equipment to perform. Not to mention that meeting API SL and ILSAC GF-3 specifications permits only a maximum of 15% motor oil evaporation.

In a test conducted where Amsoil 5W-30 Synthetic Motor Oil was pitted against Mobil 1 SuperSyn 5W-30 Motor Oil, the Amsoil oil lost only 4.9%, while the Mobil 1 variant lost 9.17% of its original weight. In layman’s terms, this means that Amsoil has a stronger resistance to boiling off at extremely high temperatures. These results may be true for only one specific oil type, but they give a pretty good idea of the capabilities of each oil brand. However, they should not generalize the performance of other Mobil 1 multi-grade oils.

Four Ball Wear

This test measures a lubricant’s wear protection properties via wear scars produced by four metal balls in sliding contact (under the test parameters). The oil or lubricant that produces a smaller average wear scar is said to provide better wear protection than its counterparts. Between the two brands, the AMSOIL 5W-30 Synthetic Motor Oil produced a smaller wear scar than the Mobil 1 SuperSyn 5W-30 Motor Oil.

Interestingly, many vehicle owners do not believe in the credibility of this test, as its parameters do not capture real-life causes of engine wear. Using 0W-30 motor oil on engines in sub-zero weather would be subject to entirely different conditions and triggers for viscosity loss compared to that of the test. RPMs are also controlled, with a ceiling of 1,800 revs. As if to prove this disbelief, it has been established in forums that Mobil 1™ Extended Performance Oil maintains its smoothness longer than Amsoil Signature Series Synthetic Oil when subjected to aggressive driving.

Flash/Fire Point

Another important bench test is the Flash/Fire Point Test, which determines the lowest temperatures at which lubricant vapors can ignite (with the application of a flame) and sustain burning for five seconds. The results of this test help consumers understand how volatile a lubricant’s characteristics are and how safe it is to transport and use. Between the Amsoil and Mobil 1 variants tested, the Amsoil 5W-30 Synthetic Motor Oil showed more stable volatility characteristics.

Pour Point

Often mistaken as the reverse of assessing a lubricant’s Flash/Fire Point, this test identifies the lowest temperature at which a lubricant can still flow. The lower the oil’s pour point, the better the performance and protection it provides in low-temperature conditions. Motor oils falling under this category also enable effortless cold starting. Based on results, Amsoil once again prevailed in this test.

Total Base Number

Lastly, we have an engine oil’s Total Base Number (or TBN). TBN measures a lubricant’s reserve alkalinity, which lends to its effectiveness in handling contaminants and minimizing the corrosive effects of acids. Amsoil has a higher TBN value versus Mobil 1. But again, the test result is only true for the 5W-30 oil grade and is unlikely to be the same for other viscosities.

Oil Types and Applications

The tables below show a list of Amsoil and Mobil 1 oil products and the intended use for each. This rundown of oil types is sure to help you determine the best lubricant for your vehicle, should you be undecided.

Amsoil Signature Series

Signature Series Synthetic Motor Oil
Viscosity: SAE 0W-20, 0W-30, 0W-40, 5W-20, 5W-30, 5W-50, 10W-30
• 75% more engine protection against wear and power output loss
• 72% better protection for turbochargers than required by the GM Dexos Gen 2 specification
• Engine protection for up to 25,000 miles or 1 year
** Values based on independent testing of AMSOIL Signature Series 0W-20 in ASTM D6891 as required by the API SN specification / 5W-30 in the GM turbo coking test
Signature Series Max-Duty Synthetic Diesel Oil Viscosity: SAE 0W-40, 5W-30,5W-40, 10W-30, 15W-40• Provides outstanding extreme-pressure and 6x more wear protection
• Maintains proper viscosity (film strength)
• Reduces oil consumption while maximizing fuel efficiency
** Claims based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation

Amsoil Premium Protection

Premium Protection Synthetic Motor Oil
Viscosity: SAE 10W-40, 20W-50
• Offers multi-functionality and wear protection for both gasoline and diesel engines
• Ideal for applications where extra protection from a higher-viscosity oil is desired – examples are modern equipment, motorcycles, motor homes, and vintage vehicles

Amsoil Heavy-Duty Synthetic Diesel

Heavy-Duty Synthetic Diesel Oil
Viscosity: SAE 5W-40, 10W-30, 15W-40
• Delivers 4x more wear protection, especially in extreme temperatures
• Minimizes oil consumption
• Great value

Amsoil Regular Synthetic

Synthetic Diesel Oil
Viscosity: SAE 0W-20, 5W-30
• Retains oil viscosity, lending to engine and 6x more wear protection
• Excels in hot and cold temperature extremes
• Minimizes oil consumption while increasing fuel economy
• Designed for smaller American diesel pickups, vans, cars and SUVs
OE Synthetic Motor Oil
Viscosity: SAE 0W-16, 0W-20, 5W-20, 5W-30, 10W-30
**Advanced Engine Protection and Performance
• Delivers 100% synthetic engine protection for advanced automotive technology like turbochargers and direct injection
• Specifically formulated for longer drain intervals (OEM-recommended)
Z-ROD® Synthetic Motor Oil
Viscosity: SAE 10W-30, 10W-40, 20W-50
• High-zinc formula protects flat-tappet cams, lifters, rockers & other critical components of classic vehicles
• Aids in retaining horsepower and protects against corrosion during storage

Amsoil XL Synthetic

XL Synthetic Motor Oil
Viscosity: SAE 0W-20, 5W-20, 5W-30, 10W-30, 10W-40
• Extra cleaning power, excellent wear control, high- and low-temperature protection, and exceptional fuel economy
• Guaranteed engine protection between oil changes up to 12,000 miles or one year, whichever comes first

Amsoil European Motor Oil

LS/FS Synthetic European Motor Oil
Viscosity: SAE Viscosity: SAE 0W-20, 0W-40, 5W-30, 5W-40
SAE 5W-40 MS Synthetic European Motor Oil*
SAE 0W-20 LS-VW Synthetic European Motor Oil**
• Meets a wide array of specifications and carries multiple OEM approvals
• Broad range of viscosities and emissions system protection keep sensitive emissions systems operating efficiently
• Specially formulated for European gasoline/diesel engines
*Engineered for vehicles requiring: BMW LL-17FE+; MB 229.71
**Engineered for vehicles requiring: VW 508.00/509.00

Amsoil Racing Oil

Viscosity: SAE 60, 5W-20, 10W-30, 15W-50
• Formulated specifically for racing & high-performance engines
• Robust formulation resists viscosity loss
• Friction modifier maximizes horsepower & torque
• Anti-wear additives provide extra protection
DOMINATOR® Synthetic 2-Stroke Racing Oil• Excellent film strength for high-heat, high-RPM engines
• Anti-friction formula for maximum power
• Burns clean and helps prevent gasket sticking and plug fouling
• Protects both coated and non-coated racing pistons
Briggs & Stratton Synthetic 4T Racing Oil• Tested and validated by Briggs & Stratton and Amsoil
• Combines heavier oil protection with the performance of a light oil
• Reduces harmful heat
• Prevents foam and corrosion buildup
Break-In Oil (SAE 30)• Formulation is sans friction modifiers, allowing for quick and efficient piston ring seating
• Contains zinc and phosphorus anti-wear additives that protect cam lobes, lifters, and rockers during critical break-in period
• Designed for new and rebuilt high-performance and racing engines

Mobil 1™ High Mileage

Brand / Type Benefits / Application(s)
Mobil 1™ Extended Performance High Mileage
Viscosity: SAE 0W-20, 5W-20, 5W-30
• Provides up to 20,000 miles of outstanding wear protection for high-mileage vehicles (cars with more than 75,000 miles)
Mobil 1™ Extended Performance
Viscosity: SAE 0W-20, 5W-20, 5W-30, 10W-30
Mobil 1™ High Mileage
Viscosity: SAE 0W-20, 5W-20, 5W-30, 10W-30, 10W-40
• Formulation specifically addresses potential problems high-mileage oils face
Mobil 1™ Full Synthetic High Mileage
Viscosity: SAE 0W-20, 5W-20, 5W-30
• Outperforms conventional and synthetic blend oils • Provides 1.5x longer protection for vehicles with over 75,000 miles

Mobil 1™ Regular Motor Oil

Brand / Type Benefits / Application(s)
Mobil 1™ Motor Oil
Viscosity: SAE 5W-20, 5W-30, 10W-30, 15W-50
• Provides exceptional wear protection, cleaning power, and overall performance
Mobil 1™ Advanced Fuel Economy
Viscosity: SAE 0W-16, 0W-20, 0W-30
• Helps improve fuel economy
Mobil 1™ Truck & SUV
Viscosity: SAE 0W-20, 5W-20, 5W-30
• Great performance in light and heavy-duty diesel trucks
Mobil 1™ Turbo Diesel Truck 5W-40
Mobil 1™ V-Twin 20W-50 Motor Oil • Outstanding performance and protection in four-cycle, V-Twin engines

Mobil 1™ Full Synthetic

Mobil™ 1 FS 0W-40
Viscosity: SAE 0W-40, 5W-50, 5W-40
• Offers excellent overall performance for latest gasoline engines and diesel engines without diesel particulate filters (DPFs)
Mobil 1™ Full Synthetic
Viscosity: SAE 0W-20, 5W-20, 5W-30
• Beats conventional oil and provides 1.5x longer protection than conventional and synthetic blend oils
Mobil 1™ Annual Protection Full Synthetic Oil
Viscosity: SAE 5W-20, 5W-30
• Guaranteed protection for 20,000 miles or 1 year between oil changes – whichever comes first
Mobil Super™ Synthetic
Viscosity: SAE 0W-20, 5W-20, 5W-30
• Outperforms conventional oils and extends engine life

Mobil 1™ European Motor Oil

Mobil 1™ ESP
Viscosity: SAE 0W-20, 0W-30, 0W-40, 5W-30, 15W-50
• Helps with the longevity and maintains the efficiency of emission systems in new, emerging diesel and gasoline powered European vehicles
Mobil 1™ Formula M 5W-40 Motor Oil• Ideal for vehicles requiring a 5W-40 viscosity and specific Mercedes-Benz approvals
Mobil Super™ Synthetic Euro 5W-40• Best for vehicles requiring a 5W-40 viscosity meeting European specifications

Mobil 1™ Racing Oil

Mobil 1™ Racing 4T Motor Oil 10W-40• Delivers racing performance for on-road, high-performance 4-stroke motorcycles

Conclusion – Amsoil vs Mobil 1: Which Is Better?

With Amsoil vs Mobil 1 independent test results, ambient temperatures, driving habits, change intervals, and budget taken into account, either oil brand proves suitable for your four-wheeler. If you are open to recommendations, experienced car owners and enthusiasts strongly suggest Mobil 1 for high-mileage vehicles and Amsoil if you are looking for a premium synthetic oil variant.

Sure, riders will have their biases. But the answer to the above question lies ultimately on you, the consumer. So long as the engine oil conforms to your vehicle’s needs and manufacturer’s specifications, you can never go wrong with your choice – be it Mobil 1 or Amsoil.