How to Pick the Best Engine Oil

Finding the Best Performance Engine Oil – Motor Oil

Car owners ask questions like  “How can I prolong my engine life?”  “How can I tell what is really the best oil for my engine, to give it maximum protection, horsepower and fuel economy?” “Does my engine oil choice really even matter?”  “How good is AMSOIL? (or Pennzoil, or Mobil 1, or Castrol, or…)”  “What oil viscosity does my car’s engine need?” “Should I use an oil additive?” And more recently, “how can I prevent LSPI super-knock from destroying my pistons?”

Thousands of vehicle owners ask these types of questions every week. And YES, your engine oil choice matters hugely. But many motor oils claim to be “the best”.  So where do you turn for solid answers?  Should you trust the race-car decals, the motor-oil bottle labels, your grandfather’s habits, online car forums, the auto-parts counter guy, your mechanic, an automotive engineer, an oil additive, or perhaps some type of oil testing?  It’s very confusing. So I will address each of those options, and explain how to know you are choosing the best oil.Is your motor oil devoted to engine protection?

In addition, a key question is “the best motor oil for what?”  Because it’s not only what the car or truck’s engine is, but also how you use the vehicle.  Mid-price oils often target one or two specific performance aspects, while meeting only the minimum requirements in all other areas.  On the other hand, some of the more expensive oils are designed to deliver superb performance in every important property. But are they really worth the extra money?  I’ll cover that important question, too.

As a former “big-3” OEM headquarters Senior Engineer with over 15 years in automotive manufacturing and design engineering, and as a mechanical engineer and lubrication specialist, my perspective is different: I assure you that this page will be very enlightening!  Frankly, even many people who you think know, or SHOULD authoritatively know what they are talking about… don’t have an entirely accurate picture.  For example, the popular 2010 Consumer’s Digest article Separating Facts from Friction is informative reading that is mostly excellent and well-balanced. But as an automotive journalist who is lacking a lubrication engineering background, the author, Dan Carney, is at times incomplete or inaccurate.  For example, he wrongly or incompletely states “you should know that synthetic oils all deliver comparable performance”.  While that is true of API-certified Group III petroleum “synthetics” that are still considered fraudulent labeling outside the United States, it’s simply not true of the high-performance Group 4 or 5 oils which are still recognized legally outside the USA as the only true synthetics.

Perhaps the single biggest problem with searching online information is the challenge of wading through petroleum oil refining perspectives and petro marketing, to separate realities from both corporate marketing and from tribal garage-guy-forum myths. For example, it’s widely believed and claimed that all oil base-stocks are petroleum oils that are refined from a 5% fraction of crude oil, which are then blended with a unique additive package.  And, any company making oil that isn’t a refiner must be “just a blender” that purchases finished base-stocks and mixes them with additives.  But those are petroleum-industry perspectives that are rooted in more than a century of fossil crude-oil drilling and refining, and they only describe refined petroleum Groups 1, 2, and the many fake “synthetic” Group III petroleum base-stock oils.

Sure, petroleum oil was a real lubrication advancement from the whale blubber oil, waxes and soaps used in the 1800’s.  (See the basics on what every lubricant must do.)  But are consumers really supposed to believe that every single facet of technology has advanced dramatically since the 1960’s… except that there is still no better lubrication science than refined crude oil?  That’s an insult to intelligence, like suggesting that 4k flat-screen TV’s are expensive over-hyped technology that has no advantages over 1980’s 19″ color CRT television sets!  Can you EVER imagine a co-worker saying “you can barely tell any difference in picture quality between a 4k OLED and a good Cathode Ray Tube TV set, and a 30 watt flat-screen vs a 300 watt CRT power-hog is no big deal – so there’s no way I would pay twice as much money to buy a 4k OLED flat-screen TV”?

That conversation never happens because consumers know better, and because the educating marketing of new TV technology is everywhere.  But automotive lubrication is different, because the global petroleum giants make enormous profits by plotting strategies to keep consumers, and entire nations, in the dark.  So allow me a few minutes to turn on the stadium lights for you in the darkened arena of lubrication technologies, because the game has been over for decades and the winning technology is clear.

REAL synthetic lubrication technology is aerospace science chemical-engineering-based: it is not geology/fossil-crude-oil/tower-layer-separation (refiner fractioning) based.  In the same way that Goretex fabric is engineered material that’s designed to beat other options (like oiled leather, waxed canvas, rubber or plastic) for breathable, durable waterproof characteristics, synthetic oils are likewise engineered to excel in lubrication.  True synthetics are designed not only to be much higher performance than what can be refined from a crude-oil fraction, but to perform like an ideal lubricant which is also highly robust – resisting breakdown during use.  The best of the synthetic oil or grease designs can literally multiply the lubricant’s service life at the same time they are cutting the mechanical wear-rate by 50 to 90%.

The manufacturers of high-performance Group 4 synthetics  “build” their own unique base-stock oil molecule designs using complex engineered recipes. They generally begin by transforming a low-viscosity “seed stock” material, which can be a range of either petroleum or bio liquids (based on pricing and availability).  Then by taking it through a proprietary series of precisely controlled chemical reactions, they build the desired molecular structure.  It is this unique chemical manufacturing of ideally-designed, uniform lubrication molecule structures that enables a range of higher performance base stocks in “true” synthetics, all of which exceed the performance of petroleum Group 3 base-stocks by varying margins.

In fact, it’s widely accepted in the Society of Automotive Engineering (SAE) that a Group IV (4) synthetic base-stock has 7 to 10 times the film strength of a petroleum oil, providing much stronger and more durable lubrication protection.  Group III (3) oils normally can and do narrow that margin of synthetic superiority, but their performance varies widely, and the truth is that they cannot completely close that inherent performance gap – especially once the oil has been running in the engine for a while.

I believe that for these reasons, petroleum oil companies try to hide or blur the facts of synthetic lubrication as much as possible. Because frankly, it is impossible to drill a synthetic oil well or to refine a Group 4 synthetic base-stock, and that’s a problem for the petroleum-lubrication business model which uses crude-oil refineries to make highly profitable use of 5% of the crude oil content.

So how can you decide on “the best engine oil?”  To explain that, let’s review each of the nine possibilities listed above, and consider the question “what should you trust?”:

  1. Race car decals:
    Racing car body decals are simply marketing agreements with sponsors, and are often not statements of what is used in the race car.  When there ARE statements of a brand that’s used in the race car engine, the exact oil is generally a specially-developed racing-only oil that is designed for a specific performance-attribute balance, contains no rust-inhibitors, is not suitable for normal vehicles and driving habits, and is not available for public purchase.  AMSOIL racing is one exception to this, because AMSOIL-decal racers really do use them, and AMSOIL’s synthetic racing oil technologies are available to anyone.
  2. Motor-oil bottle labels:
    “Ninety-five percent of the words on a can of engine oil are marketing hype,” said James Garthe, an agricultural engineer at Penn State University who has done oil testing (source: Consumer Reports article).  Correct. What’s important on the oil bottle are the Service Grades, the specifications being met, and the Group number of the base stock oil.  Rarely is the base stock Group identified on an engine oil label, despite the fact that it’s the largest determiner of both the manufacturing cost and the performance level of the oil. (That omission is not accidental, but strategic, to avoid educating consumers.)
  3. Your grandfather’s (or dad’s) habits:
    These family traditions can carry big “weight” because of engines which lasted perhaps 200,000 or 250,000, or on rare occasion even 300,000 miles, and because of personal respect. However, EVERYTHING has changed in cars and trucks – including engine designs and operating temperatures, emissions requirements, oil capacity, oil service grades, body corrosion speed, new vehicle prices, and length of car loans. Loans? When my grandfather (born in 1911) was buying his second and third vehicles, most banks still didn’t even offer car loans.  But today a car dealership is stunned, almost paralyzed, if someone wants to pay cash!  Today’s technology reality is that nearly every modern engine design is expected to last a minimum of 150,000 miles with recommended oil changes, and most designs will exceed 200,000 miles regardless of any oil brand. But shift to the other extreme of modern lubrication technology: I think you’d agree that none of our families’ traditional store-shelf motor oils would ever produce the Million Mile Van. (Yeh. Stick with me – this is going to get really good.)
  4. Online car forums:
    Online forums can be a helpful source of information, but they can also hurt consumers when the subjects are too complex to handle in these public/member discussion forums, because the communication format is a range from 4 words to 4 paragraphs.  API Certification of engine oils is one of those too-complex subjects, partly because it comes up so often in context of Warranty coverage and Synthetic lubricants – especially synthetic engine oil.  And people can be passionate about both engine oil and warranties.  Throw all four subjects together of warranty, API licensing, synthetics, and engine oil, and it’s so hard to get to the facts that many older forum members refer to them as “oil wars”.  The end result is that forum readers & members are swayed by whoever seems the most convincing, or has been around the forum the longest.

    Unfortunately, it’s very rare that the forum “gurus” are automotive engineers (and even more rare that they are lubrication specialists). The main reason for this is because most of the OEM’s monitor & specifically restrict their engineers from commenting on forums and identifying the fact that they are an OEM engineer: there is little room for tolerance, and any engineer who falls into a questionable situation risks being escorted out of the building while legal counsel is discussing corporate response options. For these and workaholic reasons, most OEM engineers rarely participate in automotive forums unless it is officially approved as part of their job (yeh, that’s rare).
    Additionally, an automotive OEM engineer who is an AMSOIL dealer cannot reveal or prove that he is an OEM engineer, yet by forum protocols he is expected to reveal that he is an AMSOIL dealer.  Otherwise he will be “outed” as a dealer, with negative consequences.  As an AMSOIL dealer many forums restrict his activity because he is not one of the paying advertising sponsors of the forum (or because true technical knowledge of synthetic oils is in opposition to the business purpose of the forum), while users accuse him of being uneducated and spouting self-serving sales bias as he tries to educate and assist them.   At the same time, anyone is permitted to support/proclaim/repeat the “conventional wisdom” of petroleum oil marketing training, with few accusations of bias or being uneducated on the subject.  (Yes: been there, done that.)  How’s that for stacking a forum environment against technical engineering facts and consumer education?

  5. Auto-parts counter guys:
    The best of them are experienced mechanics, and these gentlemen can usually steer you to some of the better quality oils.  But don’t expect much more – if they have any lubrication training that’s unusual, and it’s nearly always based on petroleum-oil marketing materials.
  6. Your mechanic:
    The better ones are SAE certified. And they are well-trained to efficiently troubleshoot and wrench on vehicles.  But again, any lubrication training is fairly rare and nearly always sponsored with petroleum-oil marketing materials. On the downside, many mechanics have developed opinionated and incorrect perspectives on engine oils, and lead their customers down a mediocre path that doesn’t provide much more than average protection for their engines.
  7. An automotive engineer:
    Some of these are an excellent resource, but which ones? And how can you find one of them to communicate with, if they aren’t allowed to identify themselves in a public forum?  Even if you find an OEM engineer, an automotive engineer who actually is well-trained in lubrication and tribology is very rare.  Over-relying on some of the available automotive engineering experts is a weakness of Carney’s article, as in this final quote from a GM engineer: “Snider says it’s a waste of money to use costlier motor oil that meets GM’s tougher [GM4781M] requirements in vehicles that don’t require it. “The best” is an inappropriate term, he says. “The best oil is that which the vehicle was designed to run on.””

    Nanofiber Overlay on Standard Air Filter Media
    Nanofiber Overlay on Standard Air Filter Media

    In reality, Snider’s “waste of money” conclusion is incorrect unless it excludes the top-performing synthetics and nanofiber oil filters. In most cases it’s a waste of time and money to use anything besides AMSOIL’s 25,000 mile / 1-year synthetic engine oils and nanofiber oil filters: by the time you consider the 2-9% fuel economy improvement, and compare that one oil/filter change per year to 2-5 oil changes, it’s far cheaper annually to use AMSOIL’s high performance synthetic technology.  And that’s before considering the automatic wear rate reduction that you get with AMSOIL’s nanofiber oil filters: GM’s own research in the ’80’s was reported in SAE Technical Paper #881825, documenting a 70% reduction in engine wear rates if technology could ever enable 15 micron efficiency in spin-on filtration. Today’s military/medical/aerospace technology does provide that capability using nanofiber filter media, and AMSOIL is the only one that has brought nanofiber filters to the automotive market.

    When you combine both AMSOIL’s premium Signature Series synthetic oils with their nanofiber EaO oil filters, a 75% wear-rate reduction is a conservative estimate of typical results.  Wait – a 75% wear-rate reduction means quadrupling mechanical life!  Is that “hype”?  Not at all.  Let’s continue, but we’ll come back to the subject of AMSOIL performance.

    In 2014 I was still a senior engineer in a Big-3 headquarters, in an engineering group where I sat within ten feet of the engineers who made all the lubrication decisions across all the vehicle platforms, including engines, differentials and transmissions.  I came to realize that senior lubrication engineers in the OEM headquarters have unfortunately been subjected to decades of targeted petroleum-industry marketing strategies (blending truth with deception) that are cleverly disguised as technology-driven, and packaged into time-saving strategic vehicle-service perspectives (which drive to the heart of common OEM concerns in supporting effective dealership servicing of the vehicles). Rarely have they obtained training from a synthetic-oil engineering group that is not chained to big-petroleum corporate objectives.  This lack of exposure allows them to be more easily guided by groups of petroleum-company engineers who are targeting them to secure OEM decisions which are most favorable to petroleum interests (a strategy aligned to the stated objective of the API).AMSOIL University Alumni

    Fortunately for you, I did get synthetic lubrication training: AMSOIL University was remarkably eye-opening, putting me on brain overload for a week.  Since then, I’ve proven to myself over and over again that AMSOIL makes the best-performing, best-protecting engine oils and vehicle lubricants, and that AMSOIL saves money. Here is a quick cost-comparison summary… (you can click on the chart for more details):AMSOIL Savings Cost Calculator 2015

  8. An Oil Additive?
    I wrote an extensive article to discuss the questions in detail, should you use an oil additive, and which additives are best?  The very brief summary: no, you should not use an oil additive.  The worst additives can harm your engine, and most of them do nothing beneficial for you.  The best oil additives do work, but they only help petroleum oil performance: by the time you add their pricey cost to petroleum oil, you are wiser to buy a better-balanced and better-performing synthetic oil.  In fact, true synthetic lubricants are the biggest secret in the automotive industry.
    Why is there even any interest in additives?  Essentially it’s because the oil additive companies bait consumers to ask the wrong question: “What can I add to my oil to get better performance?”  Better performance is actually simple: buy a better motor oil.  One engineer, Tom Stosek, summarized the situation to me this way:  “The question is, what can your lubricant do for YOU?  Satisfy minimum specifications, or achieve maximum performance?”
    The realm of petroleum oils is all about making minimum-performance high-profit oils, then marketing them to create the impression of high performance. In that realm, by excluding true synthetics, there is naturally room for some aftermarket additives to improve petroleum engine oil performance.
  9. Engine Oil Testing?
    Finally we’re here.  YES!  Absolutely, rely on test data.  Show me the data!

Any marketer can make opinion statements, emotional appeals, and unsupported claims. But DATA is where engineering battles marketing to WIN on the field of reality!

What kind of motor oil testing?  I’ll explain that, but first let me describe two examples of testing that is NOT valuable:

  1. One company sent me a college lab test to show that their product produced a horsepower increase. But it wasn’t an ASTM or SAE defined test, and it wasn’t a certified lab – just students working with an old dyno stand at the college, showing such a small HP increase that it could have been variation produced by instruments, dyno variations, humidity or air temperature.  It was no wonder the company didn’t make this test information available online – it was absolutely worthless, yet it was the best data they could offer!
  2. There are entire groups of people online who are passionately focused on chemical elemental testing of motor oils.  A single inexpensive test gives a percentage breakdown of all the elements in an oil. Then, like reading tea leaves, these groups attempt to divine performance conclusions from the data.  The problem is that, for example, Zinc content means only Zinc, and does not identify how much of that Zinc is in the more expensive high-performance ZDDP compound, and how much is just cheap Zinc thrown in.  While their data is… interesting… that approach is rather like comparing clothing brands and sizes, body measurements, or DNA samples of quarterbacks as ways to identify which college quarterbacks will be most successful in NFL Superbowls in their careers. Elemental test data is certainly valid information, but nevertheless tells almost nothing about the molecular compounds and structures in an oil, and so it provides very little correlation to real-life vehicle performance.

Legitimate oil performance testing ALWAYS uses the standardized ASTM tests: these are what the entire lubrication industry and automotive industry uses globally, constantly.

For lubricants, the ASTM tests are to the lubrication industry what an individual athlete’s game stats are to professional sports.

NFL college scouts consider performance stats like the 50-yard dash, pass completions, field goal percentages, yards per game, tackles, fumbles, and fumble recovery: on the gridiron “field of battle”, it’s the real measured performance that is the most accurate prediction of their performance potential on an NFL team.  It should be no surprise that the Society of Automotive Engineers (SAE) and the American Petroleum Institute (API) rely on specific engineer-designed tests for all automotive lubricants. ASTM tests are used extensively and almost exclusively to develop new oil formulations, AND to measure or validate oil performance, AND to develop new SAE/API Service Grades to list as the OEM’s engine oil requirements in all future owner’s manuals. (Yes, ASTM tests apply not only to North American SAE Grade oils, but also to ILSAC, ACEA and JASO.)

These ASTM tests were painstakingly devised by international teams of engineers, and improved for decades, to produce useful, measured data that correlates to performance attributes in actual application use. The tests are always performed in the same prescribed way on calibrated equipment in certified labs by certified technicians. Because the tests are carefully standardized (robustly designed for reliable repeatability by fully defining and mandating control of all the variables and calibrated accuracy of the instruments), they provide data which accurately correlates to historical test data on all other oils. Further, most of these tests are relatively inexpensive ways to demonstrate and measure superior performance advantages.

For vehicle owners, clearly one of the most important questions is this:  how can I compare and pick a motor oil that really IS high performance?

The answer: ASTM testing data lets you do exactly that, because performance in important characteristics is exactly what ASTM tests are designed to measure.

AMSOIL protects turbochargers 3 to 4 times better than Royal Purple and Mobil 1

The disturbing reality is that the lubrication industry has a “don’t ask, don’t tell” approach with consumers: they know that most consumers don’t ask for the results of the ASTM testing,  and they don’t tell consumers that these ASTM bench tests even exist (which they perform all the time and the entire lubrication industry relies on).  Nor do they share their ASTM test performance data with the public. This deliberate keep-you-totally-in-the-dark approach is perfect to enable petroleum companies to market minimum-performance products as “high-performance”, in order to make maximum profits: there are no competitive high-performance product-development and manufacturing-process engineering costs, just competitive marketing.

Fortunately, AMSOIL is the king of published lubrication test data – and not just on their own oil. In fact, AMSOIL has publicly published far more than 1o times the test data on Mobil 1 than Exxon-Mobil has.  They publish the standardized ASTM test data that was performed by independent certified laboratories, and the ASTM results are so reliable and accurate that not one of the many oil companies has dared to complain or filed a lawsuit for inaccurate test data.  They can’t, because the entire lubrication industry and the API use these exact tests.  Further, the oil companies usually rely on their own certified labs instead of independent certified labs that AMSOIL uses for published data.

AMSOIL regularly publishes standard SAE/ASTM/API test data, but because very few lubrication companies publish any performance test data besides AMSOIL, some people assume that AMSOIL invented the very ASTM tests which are used globally by the entire lubrication industry.

The deafening silence of the petroleum lubrication industry about their actual ASTM tested product performance is absolutely ridiculous!

Q: But I’ve heard that the “best motor oil depends on your application” because oils are designed differently. So how can I know which one to choose? 

A:  That’s true to an extent. But it’s also like saying the best Super Bowl team “depends”: the debate on “the best” is basically settled once the Super Bowl is played and the clock runs out – unless you play the API’s petroleum game, keeping the scoring hidden and pretending that no-one knows the winner.  Petroleum companies hide their data because when a Super Bowl is won by a 50% point margin (like 30 to 45), no-one can seriously argue that the winner “barely won” or that the losing team is the best one.  And what about when the final score is 60 Synthetic, 30 Petroleum?  That’s no problem if the score is never announced!

LSPI Super-Knock – Why Oil Additives Have Become a VERY Bad Idea

How do you protect your 2016+ turbocharged gas engine from “super-knock”, or Low Speed Pre-Ignition (LSPI) damage, which is caused by normal driving?

Vehicle manufacturers know LSPI damage in new TGDI (turbo gas direct injection) engines is a serious risk and have temporarily programmed vehicle software to “detune” the engine below the intended level of engine horsepower and fuel economy, in order to avoid LSPI-inducing conditions. Doing so, however, limits fuel efficiency.  The SAE, API, ASTM and OEM’s will soon issue a new oil grade with new tests to prove oils prevent LSPI (not a simple task).  Soon afterward, to extract maximum efficiency from their advanced power plants, OEMs will implement software updates (expected in 2019) to unleash more power and improved fuel economy, along with much higher susceptibility to LSPI. New cars sold after this will have the updates, and vehicles serviced by dealers will get the updates.

After the software installation, engines without the protection of a motor oil formulated to combat LSPI will be at great risk of severe damage.  HOWEVER, one risk which is getting little attention is aftermarket engine-oil additives.  At DMT Technical, we expect that use of oil additives will imbalance the finely-tuned oil formulations, enabling LSPI either immediately or as the engine oil ages before the next oil change, and creating a wave of super-knock engine rebuilds which WILL NOT be covered under warranty.

We are pleased with how AMSOIL has worked hard to fully prepare for these future OEM updates, protecting their car, truck and fleet customers by reformulating their product line long before new testing standards are finalized.  Proving it can protect turbocharged direct-injected engines, AMSOIL entire new line of synthetic engine oils have all achieved 100 percent protection against LSPI in the engine test required by the GM dexos1®Gen 2 specification.

Note that while dozens of oils are certified to GM’s spec, ahead of an official industry standard test, dexos1®Gen 2 certification does not require 100% LSPI protection.  Oils can have a specified number of LSPI events and STILL pass the requirement, and consumers will NOT be told how well an oil performs.  Further, because the piston-stresses of LSPI events can be severely high, they can create cumulative microstructure damage in the pistons as mileage gets higher, leading to sudden piston failure due to fatigue fractures.  For these reasons, for best protection, we recommend using only AMSOIL engine oils, and to NEVER add any oil additive to ANY engine oil in TGDI turbo’d engines.

In engine-oil designs there are big differences that I personally split into the…

Three Tiers of Engine Oil Design:  AMSOIL synthetic motor oils provide 75% Better Protection

  • The Bottom Tier is Group 2 petroleum oils that include both the bare-minimum performance oils, “synthetic blends” (Group 2 & 3), and also those petroleum oils that are designed to deliver only a specific performance improvement beyond the minimums, such as maintaining engine seals in older engines or improving cold weather starting. (Think of these oils like your grandparents’ old 13″ to 25″ fuzzy-picture, heavy, cathode-ray-tube television.)
  • The Middle Tier consists of a variety of petroleum Group 3 “synthetics”, and true Group 4 synthetics that are designed for certification under API Starburst label licensing which prohibit maximum performance.  By prohibiting maximum performance via the API’s extra restrictions (not created or required by the SAE), the API ensures that neither long-drain-interval nor low-wear-rate oils can be licensed to carry the trademarked API label symbols. This strategy helps petroleum companies to avoid competition from European and high-performance synthetic formulations in the USA’s huge-volume vehicle service market, and it enables continuation of irresponsibly short oil-drain intervals for maximum petroleum profits. (These oils are like 22″ to 39″ 720-pixel, 60 hertz LCD televisions – way better than a 19″ CRT, but not even full HD.)
  • The Top Tier is exclusively true synthetic Group 4 and/or 5 oils, and the best ones are exhaustively designed to deliver maximum performance in every characteristic of a lubricant, over long distances. (Europe has proposed a standard for 30,000 mile engine oils.)  By delivering extended drain intervals and improved fuel economy, ironically, the best top-tier synthetics become less expensive to use than petroleum oils!  And by delivering low wear rates, they can double to quadruple the remaining life of an engine compared to petroleum oils. For these reasons, petroleum companies try to pretend that these high-tech oils don’t exist, or are “hyped” to exaggerate their technology advantage.
    (High-performance synthetic oil technologies are as advanced as 60″ flat-screen televisions, ranging from economical 120 hz 1080P HD to the OLED 4k sets that seem like you are looking out of an open window at real life, and these oils cannot be manufactured with old petroleum refinery technologies any more than LED TV’s can be manufactured in CRT picture-tube TV factories.)

So what about ASTM test data comparing Top Tier synthetics?  Only one synthetic oil manufacturer publishes any significant amount of ASTM test data. Guess who? AMSOIL.

How Do AMSOIL Synthetic Engine Oils Compare Against Other Major Oil Brand’s Synthetics?

We’ve not found a single one that comes close to providing the overall protection and performance that AMSOIL synthetic oil does!  After the last decade of opportunities with many new Group 3 “synthetics” and some real Group 4 synthetics introduced to the market, even the latest independent ASTM testing in the now-crowded 5W-30 synthetic engine oil market still shows weak competition against AMSOIL’s superior performance.  (See Frequently Asked Questions about Synthetics and AMSOIL.)

AMSOIL engine oils are carefully engineered to perform at such a high world-class level that they are guaranteed to still reliably continue to meet good design performance standards at these long mileage intervals.  If ANY other motor oil is factually more durable or robust than AMSOIL, then

  1. where is the published battery of ASTM test data results, and
  2. why are shorter drain intervals recommended, and
  3. why is their performance not guaranteed at all, for any drain interval?

The stark reality is that in nearly all cases the “better than AMSOIL” claims are not backed by a single one of those three!  Isn’t that called “three strikes and you’re out”?

The “better than AMSOIL” equivalent would be a group of high-school swimmers showing up at Olympic team trials, boasting that they’re as fast or faster in the pool than Michael Phelps, but not a single one can back their bragging with a certified race time, not a single one is willing to bet money and then race the clock, and none of them claims to race further than 50 meters max.  This analogy is so realistic that I wrote an article explaining how Phelps’ gold medals prove AMSOIL’s dominance.  Like Michael Phelps, competitive AMSOIL pretenders have long been bluffing and spouting hot air – but when it’s time to post data, they are nowhere to be found.

What about Mobil 1?

Mobil 1 appeared after AMSOIL introduced their first API certified 25,000 mile oil, in order to use marketing to control the synthetic oil messaging to consumers. AMSOIL is devoted to protection Mobil 1 is a “good” synthetic oil which is widely available through standard petroleum distribution, and so has become factory fill for such high performance vehicles as Porsche, Mercedes AMG and Corvette.  Many people want to know whether AMSOIL or Mobil 1 is better, particularly when they see AMSOIL’s comparative ASTM test data against Mobil 1 and many other synthetics. (Check out those comparative scores!)

In fact, so many people wonder what Mobil 1 has to say about AMSOIL’s comparative ASTM performance data that Exxon-Mobil’s official website devotes a complete webpage to a user’s direct question and request for data, asking whether Mobil 1 or Amsoil is a better oil. They published this frequent question on their own website with a dedicated page, and optimized that page for “Amsoil” search traffic.  The Mobil 1 user, Greg Galbreath, closed with this plea all the way back in 2006:

“AMSOIL claims of 25,000 miles with fleet testing gets me thinking maybe I should change to AMSOIL. Your honest reply citing professional standards used would be appreciated by many of the public (i.e., ASTM). I really would like to know who has the best protection and why. Your reply is greatly appreciated.

His request is pointed and clear, and is used by Exxon-Mobil to represent probably thousands of similar questions they have received.  But notice and carefully consider their response.  The 4-sentance marketing answer completely avoids the question, links to a taxicab fleet video talking about how much better Mobil 1 is than regular petroleum oil, and gives no comparative data for AMSOIL, at all.  None.  Sure it was from 2006, but a November 2015 search on their website shows that there is still no other information – no test data at all – that could enable comparison to AMSOIL.

Why the marketing sleight-of-hand?  Why (for 10 years) would Exxon-Mobil have avoided answering this important and frequent decades-old question?  And with hundreds of lawyers, why would they not legally challenge AMSOIL for any of the decades of dozens of boldly published ASTM test results, unless… Amsoil’s published data is true?

The logically inescapable conclusion: 

Since AMSOIL’s test data is totally accurate and irrefutable, and Exxon-Mobil knows it, and since they are unwilling to create a better-performing product which could seriously compete against AMSOIL… a marketing bait-and-switch ploy is the best response they can create.

AMSOIL’s superior performance is NOT new.  AMSOIL has a long testing history across both consumer and racing products.  For example, the graphs on the back of AMSOIL’s Series 2000 20W-50 Racing Oil or the Series 2000 0W-30 Severe Service Oil bottles proclaimed these results to the world:

  • The 20W-50 Mobil 1 Tri-Synthetic leaves a wear scar over 2 times that of the AMSOIL (0.440 mm for AMSOIL vs. 0.922 mm for Mobil 1)!
  • Same thing goes for Havoline Formula 3 (0.713), Valvoline Synthetic (0.741), Castrol Syntec (0.757), Quaker State (0.790, synthetic blend).
  • The Mobil 1 Tri-Synthetic 0W-30 leaves a wear scar over 1.6 times that of the AMSOIL 0W-30 (0.373 for AMSOIL and 0.607 for Mobil 1)!
  • Same thing goes for Penzoil 5W-30 at 0.540, Castrol Syntec 5W-50 at 0.576, Mobil 1 5W-30 at 0.589 and Quaker State 4×4 10W-30 Synthetic Blend at 0.595.

Mobil Supersyn was a big marketing push, a new high-performance oil, yet the independent lab test data showed that Mobil Supersyn did not compare to AMSOIL’s extended drain interval 25,000 mile/1-year oil.  The test data was as follows for AMSOIL 5W-30 vs. Mobil Supersyn 5W-30:




Mobil Supersyn 5W-30


ASTM Testing Summary

(This Archive Data is for historic example.

View Most Recent Test Data)


                                         AMSOIL       Supersyn

NOACK Volatility:        4.90%             9.17%

Flash Point:              446 deg. F.      435 deg. F.

Fire Point:                 471 deg. F.     455 deg. F.

Pour Point:               – 60 deg. F.      -54 deg. F.

4-Ball Wear Test:       0.40 mm          0.60 mm

TBN (Total Base No.):  12.355             8.45


Mobil will not recommend or guarantee 25k mile/1-year drain intervals like AMSOIL 0W-30, 5W-30, 10W-30 or 10W-40 Synthetic Motor Oils. No-where on the Mobil bottle or the Exxon-Mobil website does Mobil 1 claim 25,000 miles/1-year.

AMSOIL is proven to be the best by the ASTM standardized industry tests! AMSOIL was, and still is, the “First in Synthetics”. All other synthetic motor oils came later. This is a lubrication-industry fact that NO oil company will dispute. As to the question of being #1 in quality, they’ve never challenged that fact either. {See Full ASTM test results against Mobil 1 and other synthetic oils.}

The bare truth is that up until about 2001, these petroleum manufacturers never even offered a synthetic (except Mobil1). In fact, they they had always stayed busy trying to debunk the benefits of synthetics to the average consumer! Now, technology advancement, emissions requirements, engine design, competition and consumer demand has forced every major oil manufacturer to have a synthetic, so they are now claiming the same benefits that at one time they were trying to debunk. They also claim their re-defined petroleum “synthetics” offer true synthetic performance – claims which are still considered fraud in most countries outside the United States.  Yet not a single one comes close to offering the protection and performance that AMSOIL does – not becauseSave up to 25 percent and get exclusive offers as an AMSOIL Preferred Customer PLUS exclusive help from a former OEM headquarters senior engineer they couldn’t, but because they don’t want to

SECRET:  If the oil has not broken down, and the additive package is still robust, and the wear particles are being filtered out, then changing the engine oil gives you no benefits.  (However, the money from your pocket does benefit the corporate profits of oil and filter companies, and companies providing oil change services.)

No, you do not have to use long drain intervals when using AMSOIL oil and filters.  Their 75% wear-rate reduction does not require you to extend your engine oil drain interval.  But, the fact that the oils are guaranteed for those long drain intervals and have hundreds of millions of miles of fleet Oil Analysis Sampling data, and a decade with the Texas State Highway Patrol fleet, means for certain that the AMSOIL synthetic motor oils have an extra high margin of performance above the minimum requirements of the SAE Service Grades.  We do suggest that rather than wasting your time and money on overly frequent oil changes that give no benefit, why not use those resources to address your other important maintenance issues that the auto industry keeps quiet, that would really help your vehicle life and performance?  Visit our Vehicle Oil and Maintenance page and the three biggest automotive secrets to understand the other important maintenance items you can be doing that really will make a difference and pay you back: differential fluid, transmission fluid, power steering fluid, grease fittings and brake fluid.

Bottom-line, here’s how to pick the best motor oil for your vehicle:

Go to our Vehicle Oil and Maintenance page for the simple process.  The page guides you to put in your vehicle model and year, and steps you through the various options you will see for specific maintenance on your vehicle, featuring AMSOIL lubricants and nanofiber filters as the Gold Standard in performance.  You’ll also find many valuable tips that most people don’t know.  For the very best performance engine oil for your vehicle that’s available on the market, according to the ASTM testing data, in your vehicle lookup find the AMSOIL Signature Series oil – it is usually the first oil listed. 

And if you have further questions, you can contact us at the bottom of that vehicle maintenance page. We’d be happy to help.

P.S. If AMSOIL University sounds intriguing (it is awesome), you can become an AMSOIL dealer AND attend A-U for a week in May: about $400 plus your hotel and food. OR, you can now “attend” online anytime at your own pace, for only $90-150 (USD) including Dealership fees, depending on the dealer signup options you select.  .

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UltimateSyntheticOil promotes the AMSOIL Filtration and Lubrication Gold Standards in the United States and Canada If you want to buy AMSOIL Products, visit our vehicle maintenance page, or the AMSOIL On-Line Store or download a clickable pdf e-catalog