AMSOIL vs Royal Purple Motor Oil

Protection Against Wear - The Most Critical Component!

Four-Ball Wear Test DiagramFour-Ball Wear Test (ASTM D-4172) evaluates the protection provided by engine oil under conditions of pressure and sliding motion. The size of the scar left as a result of the test determines the amount of wear protection the lubricant provides. The smaller the wear scar, the better the protection.

2008 ASTM D-4172 test results (see below) reveals that Royal Purple 5W20, 5W30 & 20W50 causes nearly 3 times the wear scar when compared to AMSOIL Dominator® Synthetic Racing Oils RD20 5W-20, RD30 10W-30 & RD50 15W50 respectively.

Our 2005 test results show nearly 2 times wear scar when compared with Royal Purple 20W50 to AMSOIL Series 2000 20W50 Racing Oil (TRO). In fact Castrol Syntec & Mobil1 Extended Performance 15W50 marginally outperformed Royal Purple.

In 2008 AMSOIL replaced the Series 2000 20W50 Racing Oil with AMSOIL Dominator® Synthetic 15W-50 Racing Oil (RD50). When the new formulation was put to the test, the results indicate 3 times better wear protection compared to Royal Purple 20W50 when AMSOIL RD50 is used.

Now let's see what is behind Royal Purple formulation & how the technology compares with AMSOIL, which has half the wear scar as Royal Purple.

AMSOIL vs Royal Purple Test Results

As you may know, Royal Purple is well known in racing circles. The chemistry they use is something AMSOIL, Inc. chooses not to use. One of their big selling points is extended drain intervals. Some additive chemicals can cause adverse conditions when used for long periods.

Royal Purple uses a different chemistry than most oils. They are one of only a handful of marketers using Molybdenum Disulfide (Moly) in their oil. Moly is a solid material, which is specifically banned by Cummins®, due to excessive valve train wear.

Moly is a processed mineral that is similar in appearance to graphite. Moly has good lubricating properties when used either by itself (in dry powder form or as an additive to oil or other lubricants). Particles of the Moly can come out of suspension and agglomerate. This can actually clog oil filters or oil lines and the rest normally settles in the bottom of the oil pan. This seems to be more likely when using extended drain intervals. In 2005, the test we ran on Royal Purple involved their 20W50 Racing oil versus our AMSOIL Series 2000 Synthetic 20W50 Racing Oil (TRO).

AMSOIL vs Royal Purple Test ResultsIn 2005 we ran two 4 ball wear tests with different parameters, a spectrographic baseline, FTIR scan and volatility tests. The Royal Purple showed a significantly high volatility rate with a 12.51% boil off rate. This compares to the AMSOIL TRO with only 4.47% volatility rating. Wear scars were also smaller with the TRO. For example the AMSOIL TRO left a .432mm scar and the Royal Purple oil left a .852mm scar. The lower the scare damage number the better! There was also a surprising difference in the viscosity index. The Royal Purple viscosity index (VI) recorded a low 129 cSt (ASTM D-445) versus 155 for the TRO. Higher viscosity index retention is crucial for a lubricant to be able to protect engine components at high stress & high operating temperatures, thus preventing metal to metal contact.

Through continuous R&D AMSOIL strives to manufacture the most advanced lubricants in the world. In 2008 AMSOIL launched an array of advanced racing oils in 3 viscosities RD20 5W-20, RD30 10W-30 & RD50 15W50. These three oils were put to the test all over again. The test results speak for themselves!

2008 Test Results Comparing Royal Purple 5W20, 5W30 & 20W50

(click on image to enlarge)
Royal Purple 5W-30 vs AMSOIL RD30 10W-30

Four-Ball Wear Test AMSOIL RD30 vs Royal Purple
Royal Purple 5W-20 vs AMSOIL RD20 5W-20

Four-Ball Wear Test AMSOIL RD20 vs Royal Purple


Royal Purple 20W-50 vs AMSOIL RD50 15W-50

Four-Ball Wear Test AMSOIL RD50 vs Royal Purple

NOACK Volatility Test (ASTM D-5800) is a Critical
Measurement of Motor Oil Quality!

Noak Volatility Test AMSOIL vs Royal Purpl vs LucasAMSOIL was the first motor oil company in North America to use the NOACK volatility test to measure motor oil quality and performance. Although competing motor oil companies initially paid no attention to NOACK results, the test has since become a critical measurement tool throughout the industry.

Originally developed and used in Europe, the NOACK volatility test determines how much weight an oil loses through volatilization. The more a motor oil vaporizes, the thicker and heavier it becomes, contributing to poor circulation, reduced fuel economy and increased oil consumption, wear and emissions.

During the test, the subject oil is heated to 302 degrees Fahrenheit (150 degrees Celsius) for a specified period, causing the lighter oil molecules to boil off. The results are reported in the percentage, by weight, of the oil that evaporates. The lower the number, the better the oil resists volatilization.

Because they are made from impure, irregular molecules, conventional motor oils are more susceptible to the effects of heat. The small, light molecules in conventional oil tend to evaporate (volatilize) as the oil is heated, leaving large, heavy molecules behind and leading to oil consumption and an increase in the oil’s viscosity (thickening). If those large, heavy molecules are chemically unstable, they may also break down and form deposits on component surfaces, further inhibiting the release of heat into the oil stream.

Because their formulations minimize the quantity of impure, irregular molecules, synthetic motor oils are generally more resistant to volatilization, allowing them to perform better than conventional oils in the NOACK volatility test. However, due to varying qualities of base stocks and additives, not all synthetic motor oils perform the same in the NOACK test.

Modern engine designs generate more heat than ever, accentuating the importance of the NOACK volatility test for determining an oil’s ability to provide an adequate level of protection and performance. More horsepower, turbo chargers and aerodynamic styling have created extremely hot environments that receive less cooling from outside air, and high heat leads to oil oxidation, deposits and thickening in conventional oils.

Because AMSOIL synthetic lubricants contain only uniform molecules, they are much more resistant to thermal and oxidative breakdown. AMSOIL synthetic motor oils help keep components free of damaging varnish, deposits and sludge.

Top quality for the current API SM motor oils specification, gasoline motor oils cannot experience a weight loss of more than 15 percent in the NOACK test. AMSOIL Synthetic Motor Oils were exceeding modern requirements over 20 years ago, while many current motor oils still have a hard time meeting this minimal requirement, increasing wear, fuel consumption and emissions.

As seen in the graph, AMSOIL 10W-30 Synthetic Motor Oil (ATM) easily passes the NOACK Test and falls well below the maximum 15 percent volatilization (burn off) rate dictated by the API SM motor oil specification, while the Royal Purple volatilization (burn off) rate is over 11 percent and the Lucas Oil FAILS the test with a volatilization (burn off) rate of over 40 percent.

What does the Experts & Agencies know about Royal Purple?

BP Lubricants Challenges Royal Purple's Claims for Synthetic Motor Oil

NAD® Recommends Royal Purple Modify or Discontinue Certain Claims

New York, NY – April 1, 2009 – The National Advertising Division (NAD®) of the Council of Better Business Bureaus has recommended that Royal Purple, Ltd., modify or discontinue certain advertising claims for it's synthetic motor oil.

NAD, the advertising industry's self-regulatory forum, examined comparative performance and superiority claims in print, broadcast and Internet advertising, following a challenge by BP Lubricants.

Claims at issue included:

  1. Independent university and industry tests document the performance gains of using Royal Purple. When compared to leading synthetic and conventional motor oils, Royal Purple typically:”
    • “Increases horsepower and torque by as much as 3%.”
    • “Reduces engine wear by as much as 80%.”
    • “Improves fuel economy by as much as 5%.”
    • “Fuel economy improvement up to 5% or more.”
    • “Reduces engine heat by as much as 10%.”
    • “Reductions in heat of up to 12%.”
    • “Reduces engine heat by as much as 10%.”
    • “Reduces emissions up to 20% or more.”
    • “Reductions in emissions of 20% or more.”
  2. “Unsurpassed”, “Unparalleled”, “Most Advanced...”
  3. “Provides Film Strength up to 400% stronger than other motor oils...”
  4. “Superior oxidation stability...
  5. “API/ILSAC Certified.”

In its decision, NAD noted that the advertiser voluntarily agreed to discontinue the claims “most advanced,” “unsurpassed performance” and “unparalleled performance,” steps that NAD found were necessary and proper to avoid confusion in the marketplace NAD noted that it appreciated the advertiser’s participation in the NAD process, especially as a newcomer to the retail automotive industry as it branches out from industrial lubricants. Further, NAD noted that testimonials included in a wide range of auto-enthusiast publications indicate that Royal Purple’s consumers are “vocally appreciative of its synthetic purple engine oil.”

However, NAD noted, anecdotal evidence based solely on the experiences of individual consumers is insufficient to support product efficacy claims, including claims related to horsepower, torque, fuel economy or engine heat. While the advertiser may quote from published articles if it provides clear and conspicuous attribution to the publisher, it may not rely on such articles to support efficacy claims for which it has no reliable independent validation.

Following its review of the non-anecdotal evidence in the record, NAD recommended that the advertiser discontinue the claims “Reduces emissions up to 20% or more.” and “Reductions in emissions of 20% or more” because the studies on which the claims were based are outdated and not consumer-relevant.

NAD recommended that the advertiser discontinue its unsupported claim that Royal Purple motor oil is “API/ILSAC Certified.”

Royal Purple, in its advertiser’s statement, said it “appreciates NAD’s review of the extensive record in this matter as well as the NAD’s recognition of the difficulty the automotive industry has with accurately quantifying performance claims based on bench tests alone as they do not accurately reflect real world results.”

The company noted that, while it believes the “tests and testimonials it supplied as evidence accurately portray the benefits of using its synthetic oil in a wide variety of applications, it defers to the NAD’s position that those tests and testimonials alone are insufficient to support specific performance attribute claims in consumer advertising.”

The company noted, as well, that it has “already made changes to its advertising in accordance with the NAD recommendations and will continue to implement NAD’s recommendations and analysis in developing Royal Purple’s future advertising.”

NAD's inquiry was conducted under NAD/CARU/NARB Procedures for the Voluntary Self-Regulation of

National Advertising. Details of the initial inquiry, NAD's decision, and the advertiser's response will be

included in the next NAD/CARU Case Report.

Article from LUBE REPORT - April 8, 2009

Truth in Advertising: BP v. Royal Purple

By George Gill

Royal Purple Ltd. was black and blue after BP Lubricants USA took it to task over advertising claims for its synthetic motor oil, finding a receptive audience in the advertising industry’s self-regulatory forum.

The National Advertising Division of the Council of Better Business Bureaus recommended Porter, Texas-based Royal Purple modify or discontinue numerous advertising claims for its synthetic motor oil, following a challenge by Wayne, NJ based BP Lubricants. The NAD examined comparative performance and superiority claims in print, broadcast and Internet advertising. In some of the advertising, Royal Purple compared its performance to Castrol, Shell, Amsoil and other motor oil brands.

NAD recommended that Royal Purple discontinue its use of consumer testimonials reporting specific performance attributes in the absence of reliable independent evidence showing performance capability.

“Anecdotal evidence based solely on the experiences of individual consumers is insufficient to support product efficacy claims, including claims related to horsepower, torque, fuel economy or engine heat,” the organization stated. “While the advertiser may quote from published articles if it provides clear and conspicuous attribution to the publisher, it may not rely on such articles to support efficacy claims for which it has no reliable independent validation.”

NAD recommended Royal Purple discontinue claims such as “Increases horsepower and torque by as much as 3 percent,” “Reduces Engine Wear by 80 percent,” “Superior Oxidation Stability” and “Provides Film Strength Up to 400 Percent.”

“If industry-standard tests or tests with carefully documented controls were abandoned, there would be no basis whatsoever for making any meaningful claims about the relative efficacy of motor oils,” BP said in its challenge.

NAD recommended that Royal Purple discontinue claims that stated, “Improves fuel economy by as much as 5 percent” and “Fuel economy improvement up to 5 percent or more” because its Environmental Protection Agency testing was inconclusive and the “Oklahoma State Study” and single cylinder Labeco CLR diesel engine testing cited in Royal Purple’s advertising was not relevant. The NAD noted the 1997 OSU Study was “outdated and nothing in the record demonstrated that the formulations of the competitors’ oils were similar to those available for sale on the market today.”

BP Lubricants said it hired the independent laboratory Southwest Research Institute, in San Antonio, to analyze power output of gasoline engines with Royal Purple Oil and with BP’s Castrol oil for comparisons.  “The results were provided to the challenger’s expert statistician who was not informed of the identity of the candidate oils,” NAD stated. “The challenger’s [BP’s] expert determined a 0.9 percent difference in power between the oils, which did not rise to the level of statistical significance, and is well below the 3 percent claim made by the advertiser.”

SwRI did additional tests to independently determine the differences in fuel economy, emissions data and engine temperature between Royal Purple and Castrol motor oils. According to SwRI, “there was no statistically significant difference between the fuel economy, emissions data or engine temperature between the two candidate oils,” NAD said.

Following its review of the non-anecdotal evidence in the record, NAD recommended that Royal Purple discontinue the claims, “Reduces emissions up to 20 percent or more” and “Reductions in emissions of 20 percent or more” because the studies on which the claims were based were outdated and not consumer-relevant.

NAD also recommended the advertiser discontinue its unsupported claim that Royal purple motor oil is “API/ILSAC Certified.” Noting that API and ILSAC licenses and certifications have many categories with different meanings, the NAD recommended that the company discontinue its claim that its synthetic oils are “generally ‘API/ILSAC Certified.’”

In fact, no Royal Purple products are certified to current ILSAC specifications.

The American Petroleum Institute licenses its trademarked Service Symbol, or ‘donut,’ for display on qualified engine oils, and also licenses the ILSAC ‘star burst’ logo for oils that meet the auto industry’s latest energy-conserving standards. In API’s online directory of licensees for its Engine Oil Licensing and Certification Program, Royal Purple has a total of 23 passenger car and diesel engine oil products listed, all licensed to use the API donut. Five of these may additionally display the words ‘energy conserving’ within the donut logo, but none of the Royal Purple products are licensable to the current ILSAC GF-4 specification and they cannot display the star burst logo.

Royal Purple also voluntarily agreed to discontinue the claims, “most advanced”, “unsurpassed performance” & “unparalleled performance” steps the NAD said were necessary and proper to avoid confusion in the marketplace.

“While Royal Purple also believes that the tests and testimonials it supplied as evidence accurately portray the benefits of using its synthetic oil in a wide variety of applications, it defers to the NAD’s position that those tests and testimonials alone are insufficient to support specific performance attribute claims in consumer advertising,” the company said in its response to NAD. “... [Royal Purple] has already made changes to its advertising in accordance with the NAD recommendations and will continue to implement NAD’s recommendations and analysis in developing Royal Purple’s future advertising.”

BP Lubricants did not return phone calls from Lube Report requesting comment on NAD’s decision.

"Our company makes the best lubricants in the World., and challenges anyone or any company to prove us wrong! That won't happen because our competitors know it's true."
Quotes by A. J. Amatuzio, President and CEO AMSOIL Inc.
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