With the popularity of turbochargers and other performance-enhancing technologies that increase heat, such as direct injection and variable valve timing, deposit control has taken on increased importance.  When exposed to increased heat, motor oils can form deposits, reducing efficiency and contributing to poor overall performance.  So how does Amsoil vs Royal Purple vs Mobil 1 perform?


AMSOIL goes head-to-head with Royal Purple and Mobil 1

Among auto enthusiasts, three brands often dominate the conversation about motor oil protection: AMSOIL, Royal Purple and Mobil 1.  Each has a history of providing solid protection. Yet, wherever enthusiasts gather, be it in online forums or car shows, when the topic of serious motor oil protection is discussed the debate often turns to which brand offers more protection.  Recently, AMSOIL enlisted an independent, third-party lab to compare the three brands in an industry-standard test that focuses on protecting turbochargers.

Independent test measures turbo deposits

The TEOST 33C test is an American Society for Testing and Materials (ASTM) bench test that simulates turbocharger operating conditions.  According to the ASTM, the test method “is designed to predict the high-temperature deposit forming tendencies of an engine oil.”  To meet the API SN Resource Conserving and ILSAC GF-5 motor oil specifications that are often recommended by vehicle manufacturers, a 5W-30 motor oil must limit total deposit formation to 30 mg or less.

The following graph shows the test results from the independent, third-party lab. This industry-standard test shows AMSOIL Signature Series 5W-30 Synthetic Motor Oil prevents deposits 4X better than Mobil1® Extended Performance and 3.6X better than Royal Purple®.

Amsoil Signature Series Oil Crushes Engine Deposits and Sludge

The results show AMSOIL Signature Series 5W-30 held deposits to well under the 30 mg limit recommended by vehicle manufacturers. Test results represent the formulations as they were available to consumers in April 2016. Formulations were coded to eliminate bias during testing, and samples were tested in random order.  An appropriate number of trials of each oil were run to produce results at or above the 95 percent confidence level when compared to AMSOIL Signature Series 5W-30 Synthetic Motor Oil.

The inside of my 350 engine was squeaky clean!

In conclusion, seeing is believing.  Check out my 930,000-mile engine tear down.    

Hopefully, this information adds a few more data points to the discussion when enthusiasts and people that care about what they drive compare notes on three of the leading brands that offer serious protection for the cars and trucks they take pride and passion in.

Get more test results here.

Amsoil synthetic oil spreads a film of oil throughout your engine and transmission:

  • Allows your engine and transmission to float on a layer of lubrication
  • Keeps your engine and transmission squeaky clean
  • Prevents sludge and varnish build-up
  • Increases fuel mileage by 4-6 percent
  • Increases engine horsepower by up to 6 percent
  • Eliminates block heaters…Amsoil stays fluid at -50 below
  • Fewer repairs and maintenance
  • Lower emissions
  • Less waste oil
  • A cooler running engine, transmission and differential
    And for you…a fatter wallet and peace of mind!

How To Purchase Amsoil Products At Rock Bottom Prices

To order products by phone…call Amsoil toll free at 800-777-7094
Monday – Friday 8 am – 5 pm CST.

Thank you for using my ID#516778 when ordering.

If you would like to tap into my Million Miles of experience here’s my number (937) 417-1127.

I’ll be glad to help you match up the correct oil and filters for your vehicle or equipment. If you get my voicemail, leave your name and phone number and I’ll call you back asap.

Happy Trails
John Schlimmer
www.MillionMileChevy.com