Amsoil vs Royal Purple
& Mobil 1 Deposit Test
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Buy Amsoil Synthetic Oil At Wholesale Price
Choosing the right synthetic motor oil can be a challenge with so many brands claiming top performance. In this hands-on Amsoil vs Royal Purple & Mobil 1 comparison, we look directly at independent lab testing data.
Specifically, we evaluate how each formula handles deposit control at high temperatures to determine which oil truly dominates the competition.
Modern technologies like turbochargers and direct injection increase engine heat, making deposit control more important than ever.
When exposed to extreme temperatures, motor oils can form sludge that robs your engine of performance and efficiency.
In this independent Amsoil vs Royal Purple & Mobil 1 deposit test, we break down the data to see which synthetic oil offers the ultimate protection.
Amsoil vs Mobil 1 & Royal Purple:
The Ultimate Deposit Test Results
In independent ASTM D6335 testing (TEOST 33C), motor oils are evaluated for how many milligrams (mg) of high-temperature deposits they leave behind.
A lower number means a cleaner turbocharger and a longer engine lifespan.
| Synthetic Motor Oil Brand | Total Deposits (mg) | Performance Margin |
|---|---|---|
| Amsoil Signature Series 5W-30 | 7.0 mg | 🏆 Test Winner |
| Royal Purple High Performance | 25.4 mg | 3.6X more deposits than Amsoil |
| Mobil 1 Extended Performance | 28.2 mg | 4.0X more deposits than Amsoil |
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 at car shows, when the topic of serious motor oil protection comes up, 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.
Amsoil vs Royal Purple & Mobil 1 Deposit Test
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.
Based on the independent, third-party lab results (specifically, the ASTM D6335 TEOST 33C test required by the API SN Resource Conserving specification), Amsoil Signature Series 5W-30 Synthetic Motor Oil proves to be highly effective at controlling high-temperature deposits on turbochargers.
Here is the information broken down in a bulleted list for easy reference.
- Amsoil Signature Series 5W-30 prevents harmful turbocharger deposits 4X better than Mobil 1 Extended Performance 5W-30.
- Amsoil Signature Series 5W-30 prevents harmful turbocharger deposits 3.6X better than Royal Purple API 5W-30.
- Test Standard: These results are based on the industry standard ASTM D6335 test.
- Performance Metric: The tests simulate extreme heat conditions, showing Amsoil maintained superior cleanliness, essential for turbocharger longevity.
The data strongly support Amsoil’s reputation for keeping engine parts cleaner under high heat conditions compared to major competitors.
Amsoil Crushes Engine Deposits and Sludge
My 930,000 Mile Chevy Engine Teardown
Independent lab tests prove Amsoil works on paper, but my engine proves it on the road.
I drove my ’99 Chevy van over 930,000 miles using Amsoil Signature Series oil, changing the oil every 20,000 to 25,000 miles. A valve keeper wore out (not oil-related) at 930,599 miles.
I replaced the engine and called Amsoil Corporate. They took the engine to an independent machinist, who disassembled it and inspected it for wear and deposits.
The internal components were completely free of sludge and carbon deposits and had less than 1% wear on all internal parts.
- ✔
The Result: Industrial-strength protection that delivers long engine life. - ✔
Visual Evidence: Zero stuck rings, pristine cross-hatching, and clean oil passages.
View My 930,000-Mile Teardown Photo Brochure →
Opens the official, high-resolution component inspection PDF file
Amsoil vs Royal Purple &
Mobil 1 Deposit Test
Get more test results here.
Amsoil synthetic oil forms a protective barrier
- 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
- Extreme Cold Protection…Amsoil remains fluid up to -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!
Buy Amsoil Synthetic Oil At Wholesale Price
Have questions? Need help selecting the right oil and filters for your vehicle or equipment?
Feel free to contact me anytime at (937) 417-1127 or jbs777@gmail.com. If you reach my voicemail, leave a message or text, and I’ll respond as soon as possible.
Happy Trails
John Schlimmer
Independent Authorized Amsoil Dealer
www.MillionMileChevy.com
