How does AMSOIL Signature Series compare to XL level of AMSOIL motor oil. This is a good question since AMSOIL offers 3 Tiers or levels of gas motor oil. We’ve already compared OE and XL levels in this article we wrote previously. Let’s take a look at how Signature Series compares to the XL level.
The difference in AMSOIL Signature Series and XL Motor oils begins with the use a 100% synthetic base stock. What further makes them different, is the different types of additives in different combinations to create oils for different customer needs.
Each customer market has different performance requirements they place on the oil the use. While signature Series and XL motor oils both have exceptional performance properties, it’s hard to directly compare them because the markets they are designed for are different.
Reading further will give you an understanding of how signature series and XL products compare and how they differ. Also, here is an article we wrote that talks about how XL and OE compare for even more comparison.
Signature Series motor oil goes the highest step and uses the best premium quality additives on the market to create an oil with the best anti wear, heat protection, sludge prevention, cleaning power and other properties. AMSOIL signature series motor oils are for those people who want the ultimate engine protection with 25,000 mile / 1 year oil change intervals and the best warranty on the market.
XL Level oils also use a 100% synthetic base stock like Signature Series, but it has a different makeup of additives. It’s these differences in additives that its market desire. XL Oils use high quality additives, just not the most expensive. AMSOIL XL tier oils are for those people who want to enter the high quality synthetic Motor oil Market, but aren’t sure about the protection qualities and extended drain intervals. XL’s “Boosted” oils are great for people like me, who are skeptical, but are willing to give it a try. XL oils give you great anti wear, heat protection, sludge prevention and cleaning power while providing for up to 12,000 mile / 1 year oil change intervals.
So let’s talk a little more detail about how Signature Series compares to the XL Tier of oil.
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Wear Protection
Signature Series was tested by Independent labs to industry test standards and shown to provide 75% more wear protection than minimum industry requirements for the API SN plus Spec. Signature series Motor oil was tested using the Sequence IVA Engine test to simulate extended stop and go driving, that create significant engine wear. The cam lobes are then measured in 84 spots to determine what type of wear damage is caused. Using the lightest viscosity Signature Series oil, 0W-20, AMSOIL recorded its 75% protection score.
The Wear protection qualities of Signature Series oil gives you the longest lasting engine components. This helps you extend the life of major components of your vehicle while reducing the expenses of maintenance on those parts.
Heat protection
Signature Series Motor oils were independently tested using GM’s turbo coking test for the GM Dexos1® Gen 2 spec. The results were impressive. Signature series held average turbo temperature increase to only 3.6% and the required turbo temp increase to pass the GM Dexos1® Gen 2 spec is 13% or less.
Viscosity protection
AMSOIL Signature Series Oils are formulated to resist thermal breakdown also helping to protect engines from the effects of heat. This reduction in oil breakdown helps prevent oil thickening and sludge build up. This keeps engine parts properly lubricated.
This is important because today’s automotive engines are more compact in size, produce more horsepower with turbo’s and recirculate exhaust to help with emissions control, leading to more heat inside the engine.
The sequence IIIH test uses temperatures of 304 degrees, 100 degrees more than normal, to help determine an oils ability to resist thickening caused by heat. The spec allows for 150% increase in viscosity of an oil to pass the test and AMSOIL’S signature series passed with only a minimal 6% increase in oil viscosity.
Limiting the increase of heat in engines reduces the temperature of the oil and In turn reduces the increase of viscosity in oil. This further reduces the formation of sludge and varnish on parts from extreme heat, reducing horsepower loss and wear from deposit formation throughout the oil change drain interval.
Cleaning power
Signature series Oil contains 50% more cleaning additives than the OE level oil. Detergents and dispersants are additives that help clean an engine and also help to keep the deposits, that do form, in the oil from sticking to parts until the oil is changed.
The Sequence VG Engine test puts an engine oil through 216 hours of sludge forming conditions. To pass, an oil can only allow a max of 10% blockage of the oil pick up screen. AMSOIL Signature Series kept the screen almost deposit free. This resulted in performing 90% better than industry standards.
OIL Consumption
An oil is tested Using the NOACK Volatility Test to determine how much evaporation or burn off occurs. AMSOIL signature Series had a 5.8% loss compared to the industry standard of 15%. What this means is you won’t have to “top off” your oil as much as other oils and also reduced emissions.
LSPI Protection
LSPI or low speed pre ignition, is a piston destroying condition caused by the high temperatures inside the combustion chamber of modern engines. The high temperatures are causing fuel mixture in the chamber to ignite before it’s supposed to. This is leading to piston damage and the ruining of an engine. AMSOIL Signature Series had a 100% prevention of LSPI events in all tests required by the GM dexos1® Gen 2 spec.
In fact, all AMSOIL motor oils were one of the first oils to achieve 100% protection from LSPI.
How does AMSOIL XL motor oil compare?
First, understanding that the XL line of motor oils are designed for a different customer market is important. They don’t use the same additive package as Signature Series does. What I mean is, all of AMSOIL’s motor oils are high quality, but are manufactured to meet the needs of a different customer group, which makes a direct comparison difficult. So comparing to industry standards is better.
The XL “BOOSTED” lineup is a high quality premium synthetic motor oil designed for those customers who want to try out a high quality synthetic motor oil. These customers are beginning to venture into extended drain intervals, but aren’t quite ready for Signature Series 25,000 mile drain interval.
In the oil breakdown tests, XL had a 36% viscosity increase during testing for the GM Dexos 1® Gen 2 spec. This is 64% better than industry standards to resist oil breakdown, prevent wear and deposit formation.
The XL line of motor oils have a 25% increase in detergents in its formulation compared to Signature Series 50% increase. The XL tier of oils provide high quality cleaning power and sludge prevention, but not at the same power as signature series and designed for XL’s 12,000 mile / one year service interval.
XL oils, just like Signature Series, have a 100% prevention rate of LSPI events.
What all this means to you is that no matter which tier of AMSOIL Synthetic motor oils you choose to use, you get a high quality synthetic motor oil. A motor oil that provides great protection for you engines, giving you the best opportunity to extend the life of your valuable equipment. The only real difference is how long you feel comfortable driving before changing your oil.
Related Questions
Is AMSOIL API Certified? – AMSOIL XL and OE Product lines are API Certified and Signature Series meets all the testing requirements. Due to the costs of testing and licensing each new formula, AMSOIL has chosen not license each and every product.
AMSOIL continually develops new formulations to stay ahead of engine design technology advancements and the cost to certify each new formulation is not sustainable. Also, API only certifies for industry minimums and does not test for the higher standards AMSOIL oils are designed for.
Why is AMSOIL Expensive? – AMSOIL makes 3 levels of products: Signature Series, XL and OE. Each product line has a different price point due to the quality of the additives and the customer market it is designed for. AMSOIL’s XL and OE product lines cost the same as common brands found on the shelves of mass marketed parts stores.
Signature Series, while it is higher priced, gives you the extra protective qualities and extended drain intervals that other brands won’t consider. This product line uses the highest quality additives on the market, which costs more to make. You actually save money over the long run, by not having to change your oil as much as lower quality brands.
If you were to become a preferred customer, the cost of AMSOIL products then becomes cheaper than the common brands found at auto parts stores and the shelves at WALMART.
