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Signature Series Motor Oil Protects Engines From Low-Speed Pre-Ignition

SIGNATURE SERIES Protects Engines from Future Industry Problem

LSPI can destroy pistons and connecting rods, bringing an engine to a standstill in seconds. Original equipment manufacturers (OEMs) like General Motors (GM)* have addressed the issue by designing tests to gauge a motor oil’s ability to prevent these destructive events. Signature Series achieved 100 percent protection against LSPI1 in the industry-standard test.

OEMs have been aggressively downsizing engines to meet strict fuel economy and emissions standards while improving power and torque. Most new engines today use some combination of turbochargers, direct-fuel injection and variable valve timing to make more power than their larger counterparts while delivering improved fuel economy.

This scenario seems like all upside for drivers. But today’s smaller, hotter-running engines pose significant challenges to lubricants. The latest is a phenomenon called low-speed pre-ignition (LSPI), also known as “super knock,” which can destroy pistons and connecting rods.

What Is LSPI?

LSPI is another version of engine knock, which has been around since engines were invented. In this case, it occurs under low-speed, high-torque conditions in turbocharged gasoline direct-injected engines – like when you’re taking off from a stoplight. LSPI is the spontaneous ignition of the fuel/air mixture prior to spark-triggered ignition. This form of pre-ignition is more destructive than typical engine knock.

No Magic Bullet

Just as your engine relies on a balanced network of components to function, the motor oil needed to protect it requires additives with the right qualities at the right quantities. While adding more of one ingredient or reducing another seems simple enough, small composition changes can have big impacts. We were determined to find a solution to the LSPI problem without sacrificing the performance of Signature Series in any way.

GM LSPI Test

OEMs like GM have addressed the issue by designing tests to determine a motor oil’s ability to prevent LSPI. The GM LSPI Test records the number of peak pressure events during high-load operation in a turbocharged engine over a five-hour period. Passing the test is required to meet the GM dexos1® Gen 2 specification.

Perfect Score

We armed Signature Series with an advanced detergent system that protects against harmful deposits and LSPI. Signature Series Motor Oil achieved 100 percent protection against LSPI in the engine test required by the GM dexos1 Gen 2 specifications – zero occurrences were recorded throughout five consecutive tests.

API SN PLUS Specifications

API SN PLUS is a recently released specification that was requested by the automobile industry to protect passenger vehicles from LSPI. AMSOIL anticipated this change, and the current formulations of Signature Series, XL and OE synthetic motor oil all meet or exceed the specification. Look for updated product labels featuring the new API “donut” in the near future.

Your customers can be confident that AMSOIL synthetic motor oils protect their modern engines against LSPI, helping their vehicles deliver years of reliable service. For more information on the dangers of LSPI, visit www.amsoil.com/lspi.

 

Example of piston damage due to an LSPI event observed during the testing of a competitor’s motor oil. The red arrows indicate sections of the ring land that have broken away from the piston.

Achieved 100% Protection Against LSPI1

Signature Series Battles Sludge

Signature Series Battles Sludge

The health of your engine depends on motor oil circulating quickly and efficiently through the system, but sticking components and obstructed passages inhibit motor oil from lubricating, cooling and protecting your engine. Engine “sludge” occurs when oxidized oil and contaminants build up on engine surfaces. It can restrict the flow of oil to the point of engine failure and costly repairs.

Warehouse note: The so called “fully synthetics” which are mostly group III’s or a combination of a majority group II and a fraction III ($3.50 synthetics)  to a majority III and a fraction of IV ($8.50 synthetics) – all based on price and what the stock holders allow to be used for a desired profit.. Note that all of these WILL leave deposits in the form of sludge. Turbocharged engines must avoid these brands which include the silver one shaped like a shampoo bottle. 

Sludge: Where It Starts & How It Ends

  • The valve cover and oil pan are generally the first areas sludge appears.
  • The oil pick-up tube screen is often the next spot it accumulates, impeding oil flow through the system.
  • What begins as a thin film of lacquer or varnish deposits eventually bakes into an expensive mess.

 

The Sequence VG Engine Test

Engine failures due to sludge are often caused by a clogged pick-up tube screen – the motor is effectively starved of oil. The Sequence VG Engine Test determines how well an oil resists sludge formation and keeps the lubricant flowing freely throughout the system. The test is required for API SN PLUS – a specification recommended by most domestic vehicle manufacturers.

TEST PARAMETERS

 

Engine Ford* 4.6L V-8
Duration 216 hours
Measures Sludge and varnish deposits, piston ring sticking, clogged oil pump screens and roller pin wear
Simulates Taxi, delivery or commuter vehicle service
Requirement Oil pick-up tube screen limited to 10 percent blockage

 

The Results

Signature Series Synthetic Motor Oil was subjected to the Sequence VG to measure its ability to prevent sludge. As expected, Signature Series produced an oil pick-up tube screen virtually free from sludge (see image). Our unique combination of detergents and high-quality base oils control oxidation and sludge to keep engines clean and efficient.

 

Signature Series has 50 percent more detergents1 to help keep oil passages clean and promote oil circulation. It provides 90% better protection against sludge2.

Warehouse Note: Thankfully our efforts here in Sioux Falls have made the Signature Series our top seller and on the minds of many who want their investment to remain like new beyond 250,000 miles. People are realizing that it’s not all about change frequency as a non “true synthetic” can cause damage in just 10 miles in GDI engines due to LSPI.. Not to mention why I adopted AMSOIL back in the day – the added power and performance!!

1 vs. AMSOIL OE Motor Oil
2 Based on independent testing of AMSOIL Signature Series 5W-30 in the ASTM D6593 engine test for oil screen plugging as required for the API SN PLUS specification.
*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are developed by AMSOIL for use in the applications shown.