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ILSAC GF-6, API SP & dexos: Making Sense of New Oil Specs.

ILSAC GF-6, API SP & dexos: New Oil Specifications

As engine-operating conditions grow more severe, so do the demands placed on your motor oil. Hence the need for updated oil specifications, like ILSAC GF-6, API SP and GM dexos1 Gen 2.

New engine hardware such as turbochargers, direct injection and variable valve timing (VVT) place increased stress on your engine oil. This, in turn, has led to the introduction of more strict more oil specifications.

Here’s what we’re going to cover:

  • How strict fuel-economy standards increase engine stress
  • What is LSPI (low-speed pre-ignition)?
  • How motor oil helps prevent LSPI
  • ILSAC GF-6, API SP and GM dexos
  • Do AMSOIL synthetic motor oils meet GM dexos, ILSAC GF-6 and API SP specs?

 

Improved fuel economy

Corporate Average Fuel Economy (CAFE) standards require a fleet-wide average of about 40 mpg by 2026 in the United States.

To meet these requirements the automotive industry has focused on smaller, more fuel-efficient engines. In fact, most new vehicles now feature gasoline direct-injection (GDI), a turbocharger or both (T-GDI).

Severe operating conditions

Smaller, more-efficient engines that make the power and torque of higher-displacement engines undergo more severe operating conditions that can lead to…

  • Severe engine knock, also called low-speed pre-ignition (LSPI)
  • Increased engine temperatures
  • Compromised fuel injectors
  • Increased wear and deposits if the oil isn’t up to snuff

The biggest motor-oil-related challenge on the horizon is LSPI, which can destroy pistons and connecting rods.

LSPI can cause cracked pistons and rods

LSPI is the spontaneous ignition of the fuel/air mixture before spark-triggered ignition.

It is another version of pre-ignition. Pre-ignition (engine knock) has been around since the beginning of internal combustion engines.

LSPI, however, occurs under low-speed, high-torque conditions, such as taking off from a stoplight in T-GDI engines.

This scenario can create conditions where the fuel/air ignites too early in the combustion cycle, throwing off the engine’s timing.

The expanding combustion charge collides with the piston as it’s moving up the cylinder, potentially destroying the pistons or connecting rods.

Oil can help prevent LSPI

Experts suggest the cause is due in part to oil/fuel droplets or deposits in the cylinder igniting randomly. The droplets and deposits contain enough heat to ignite the air/fuel mixture before spark-triggered ignition.

Oil formulation can play a role in reducing LSPI.

Certain motor oil ingredients can promote LSPI, while others can help reduce it. It’s tempting to think, “Well, dump a bunch of ingredients into your formulations that help reduce LSPI.” But some ingredients that help reduce LSPI have been limited over the years in motor oil formulations for other reasons.

It truly is a scientific balancing act confronting oil formulators. It’s no easy task to formulate motor oils that deliver excellent wear protection, resist the increased heat of turbocharged engines, prevent deposits, act as a hydraulic fluid and, now, combat LSPI.

The performance of the entire formulation – not just one or two ingredients – is what counts.

ILSAC GF-6, API SP and GM dexos

Next-generation motor oils need to pass an LSPI test to meet these new demands.

General Motors was first out of the gate and required oils to pass its own LSPI test. Its GM dexos1 Gen 2 specification took effect Aug. 31, 2017.

The latest American Petroleum Institute (API) specification, API SP, took effect in May 2020. As did ILSAC GF-6, the latest spec from the International Lubricants Standardization and Approval Committee. For the most part, it mirrors API specifications.

ILSAC has set a new precedent in the passenger-car motor oil market by splitting its specification into two parts. One of the main differences between the two specifications is compatibility.

See the chart below. Both versions focus on wear protection, prevention of LSPI and improved engine cleanliness. However, GF-6B features a more stringent fuel economy test.

Engine oils can easily be identified as ILSAC GF-6A or 6B by the API emblem on the front label of the packaging. A shield represents the GF-6B specification, while the traditional starburst indicates a GF-6A product.

Both ILSAC specifications meet the industry-standard API SP specification which is most commonly found in owners’ manuals.

Relax…for now

For now, you don’t have to worry too much about LSPI.

Your vehicle’s computer is programmed to avoid operating conditions that lead to LSPI. But, operating your engine under those conditions does promise fuel economy gains.

AMSOIL meets the latest specs

AMSOIL synthetic motor oils meet or exceed the latest industry standards, including ILSAC GF-6, API SP and GM dexos1 Gen 2.

You can safely use our synthetic motor oils in engines that call for those specifications.

In fact, AMSOIL achieved 100 percent protection against LSPI in the engine test required by GM’s dexos1 Gen 2 specification.*

*Based on independent testing of Signature Series 5W-30, XL 5W-30 and OE 5W-30 in the LSPI engine test as required for the GM dexos1® Gen 2 specification.

Figuring out Engine Knock

Why Does My Engine Knock? 3 Possible Explanations.

There are a few different reasons your engine might make a knocking, ticking or pinging sound. Let’s break each down and talk about what might be happening.

Is it an engine knocking sound, tick or ping?

One driver’s knock is another driver’s tick. Or ping. Still others compare the engine knocking sound they hear to marbles rolling around inside a coffee can.

The spontaneous ignition of air/fuel inside the cylinders is a common source of engine knock.

While the description of the sound may differ, the circumstances under which it occurs are often the same – low-speed, high-torque conditions common when you’re accelerating.

Engine knock typically occurs during low-speed, high-torque conditions, like when you’re accelerating.

How engine knock occurs

Say the clock has struck 5:00 and you make a bee-line to your truck and take off for home. When you mash the accelerator out of the parking lot, that’s when you hear an engine knocking sound. Or ping. When you let off the gas, it goes away.

This is likely due to either pre-ignition or detonation. They’re effectively the same phenomenon, but they occur at different times.

In a properly running engine, spark-triggered ignition typically occurs a few degrees before the piston reaches top dead center (TDC). This careful timing ensures the downward force of the exploding fuel/air mixture works in tandem with downward piston momentum, resulting in optimum efficiency and power.

That’s bad timing

Pre-ignition (and its cousin, low-speed pre-ignition [LSPI]) are abnormal combustion events that throw off this precise balance. Under certain conditions, the fuel/air can spontaneously ignite too early in the combustion cycle. Sometimes low-octane fuel is to blame; sometimes it’s deposits on the piston crown.

Fuel with too low an octane rating for your engine can sporadically ignite prior to the piston reaching TDC.

Or, chunks of carbon can heat up and create a hot spot that effectively ignites the fuel/air before the plug fires. Then, when the plug does fire a fraction of a second later, the two flame fronts collide. In certain conditions, they can clash with the upward-moving piston. The resulting shock wave rattles the piston inside the cylinder, creating the knock, ping or can-of-marbles sound you hear.

Detonation has the same effect, except it occurs after the plug fires.

Computers in modern vehicles can detect engine knock and compensate by adjusting engine timing. Though it saves your engine from destroying itself, performance and fuel economy can suffer.

Tick, tick, tick

Say your engine is ticking like a time bomb, especially in the morning when it’s cold. You likely have a valve-train issue.

Your engine uses intake valves to feed clean air into the cylinders and exhaust valves to kick spent combustion gases out. The valves open and close thousands of time per minute in a choreographed whirlwind of activity.

top dead center valve timing

A finely balanced system of parts – rocker arms, valve stems, cam lobes, lifters – control their movements. The clearances between these parts, known as lash, can become loose (or sloppy, in automobile nomenclature). When that happens, all those moving parts clattering against each other can create a ticking sound.

It’s especially noticeable in the morning before the oil has had a chance to circulate throughout the upper end of the engine.

Many engines use hydraulic lifters, which use an oil-pressure-assisted plunger and spring to compensate for lash, helping ensure the system runs smoothly and quietly.

Proper oil pressure plays a big role in valve-train operation and noise. Low oil pressure can reduce the effectiveness of hydraulic lifters, increasing lash. This is most likely to occur with a low-quality conventional oil that thins at high temperatures, preventing the engine from developing good oil pressure.

If the rods are knockin’…

Rod knock is yet another possible explanation for your engine knocking sound.

Your engine is built with a designed clearance between the crankshaft journals and the connecting rods. In a properly running engine using a good oil, the motor oil fills those clearances and prevents metal-to-metal contact.

But, let’s say you’ve been using a poor-quality conventional oil.

At high temperatures, the oil thins and the fluid film weakens. The pressure between the crank journals and connecting rods squeezes the oil from the clearances. Now, metal is riding on metal, wearing the surfaces and widening the clearances. Eventually the clearances widen so much that you begin to hear the metal surfaces clattering against each other. Eventually, they’ll weld together and destroy the engine.

Quieting a noisy engine

This all sounds dire. But you can sometimes address pre-ignition by using a higher octane gas or by cleaning deposits from your engine with a fuel-system cleaner like AMSOIL P.i. Performance Improver.

Buy AMSOIL P.i.

Using a higher-quality oil that flows better in cold weather and maintains its viscosity when hot can sometimes quiet a valve-train tick.

Shop AMSOIL Synthetic Motor Oil

Rod knock is the worst of the three. Once the clearances between the crank journals and connecting rods have widened due to wear, it’s just a matter of time before catastrophic damage.

In any case, visit your mechanic and take care of the problem before it gets worse.

The bottom line…

The moral of the story is simply to pay a little more now to maintain your vehicle rather than spend a lot later to fix it.

Use a high-quality oil that stands up to extreme heat and maintains correct oil pressure. Periodically clean combustion chamber deposits with a fuel additive, such as AMSOIL P.i.

Doing so can help keep your vehicle running properly and quietly for years.

New Motor Oil Specs are Coming

New Motor Oil Specs are Coming

As engine operating conditions grow more severe, so do the demands placed on your motor oil. New engine hardware such as turbochargers, direct injection and variable valve timing (VVT) place increased stress on your engine oil. You may find yourself asking, why do we need new engine hardware? What’s wrong with the tried-and-true equipment that has worked for years?

Well, automakers need every fuel economy gain under the sun they can get to meet tightening fuel-economy standards. And these new technologies help them get there.

More strict CAFE standards

The current corporate average fuel economy (CAFE) standard requires a fleet-wide average of 54.5 mpg by 2025 in the United States, a five percent annual improvement. These requirements have spurred the automotive industry to turn to the hardware mentioned above to build smaller, more fuel-efficient engines. In fact, by 2020, industry experts predict that almost every new vehicle will feature direct-injection technology (GDI). The vast majority will also be turbocharged (TGDI).

All upside, right?

Smaller, more-efficient engines that make the power and torque of their higher-displacement counterparts is all upside, right? In theory, maybe. But, in reality, today’s advanced engines undergo more severe operating conditions that can lead to…

  • Severe engine knock, also called low-speed pre-ignition (LSPI)
  • Increased engine temperatures
  • Compromised fuel injectors
  • Increased wear and deposits if the oil isn’t up to snuff

The biggest motor-oil-related challenge on the horizon is LSPI, also known as severe engine knock. LSPI can destroy pistons and connecting rods.

What is LSPI?

LSPI is the spontaneous ignition of the fuel/air mixture before spark-triggered ignition. It is another version of pre-ignition. Pre-ignition (engine knock) has been around since the beginning of internal combustion engines. LSPI, however, occurs under low-speed, high-torque conditions in TGDI engines, such as when taking off from a stoplight. This scenario can create conditions where the fuel/air ignites too early in the combustion cycle, throwing off the engine’s timing. The expanding combustion charge collides with the piston as it’s moving up the cylinder, potentially destroying the pistons or connecting rods.

How Does LSPI Occur?

Experts suggest the cause is due in part to oil/fuel droplets or deposits in the cylinder auto-igniting randomly. The droplets and deposits contain enough heat to ignite the air/fuel mixture before the spark-triggered ignition. This means oil formulation can play a role in reducing LSPI.

Testing has shown that certain motor oil ingredients can promote LSPI, while others can help reduce it. It’s tempting to think, “Well, dump a bunch of ingredients into your formulations that help reduce LSPI!” But some ingredients that help reduce LSPI have been limited over the years in motor oil formulations for other reasons.

It truly is a scientific balancing act confronting us oil formulators. It’s no easy task to formulate motor oils that deliver excellent wear protection, resist the increased heat of turbocharged engines, prevent deposits, act as a hydraulic fluid and, now, combat LSPI. The performance of the entire formulation – not just one or two ingredients – is what counts.

Coming Soon: New Oil Specifications

Difficult or not, next-generation motor oils will need to fight LSPI. In fact, they’ll need to pass an LSPI test to meet the new API SP and ILSAC GF-6 performance specifications set to take effect in mid-2019. General Motors is ahead of the game and requires oils to pass its own LSPI test. Its updated GM dexos1 specification (known as dexos1 Gen 2) is scheduled to take effect Aug. 31, 2017. The table explains the specs in a little more detail.

Relax…for now

For now, you don’t have to worry too much about LSPI. Your vehicle’s computer is programmed to avoid operating conditions that lead to LSPI. But, operating your engine under those conditions does promise fuel economy gains. And, once oils hit the market that combat LSPI, you can bet the vehicle manufacturers will reprogram their vehicles to take advantage in their never-ending quest for better fuel economy.

AMSOIL Prepared for the Change

We’ve been hard at work reformulating Signature Series Synthetic Motor Oil, XL Synthetic Motor Oil and OE Synthetic Motor Oil to address LSPI. The early signs are exciting. Experimental formulations of AMSOIL synthetic motor oils provided 100 percent protection against LSPI in turbocharged direct-injected engines.* Expect to see them hit the market in the months ahead.

Check out this page to learn more about LSPI.

*Based on the engine test required for GM dexos1 Gen2 specification.

ADVANCED ENGINE TECHNOLOGY DRIVING CHANGES FOR GASOLINE OIL SPECIFICATIONS

ADVANCED ENGINE TECHNOLOGY DRIVING CHANGES FOR GASOLINE OIL SPECIFICATIONS

Tightening fuel economy standards and the subsequent advances in engine technologies are pushing big changes in the passenger car motor oil (PCMO) market.

Increasingly strict regulations on fuel economy and emissions have pushed the automotive industry to develop smaller, more efficient engines. By 2020, industry experts predict that nearly every new vehicle will feature direct-injection technology (GDI), and the vast majority will be turbocharged (TGDI). The most recent corporate average fuel economy (CAFE) standards require a fleet-wide average of 54.5 mpg by 2025 in the United States, necessitating a 5 percent annual improvement.

These factors contribute to the following:

  •  Severe engine knock, also called lowspeed pre-ignition (LSPI)
  •  Increased engine temperatures • Compromised fuel injectors
  •  Greater overall stress and dependence on engine oil

Two new gasoline engine oil specifications are in development to address these issues: General Motors’ (GM)* proprietary dexos1™: 2015 and API SP/ILSAC GF-6.

Controlling LSPI

Both specifications place a major focus on limiting the impact of low-speed pre-ignition (LSPI). This will be an essential feature of engine oil in the coming years. Similar to traditional engine knock, LSPI occurs when fuel/air spontaneously ignites prior to the spark ignition. The pressure created by this ill-timed combustion pushes down on the piston as the connecting rod and crankshaft work to move it upward. These conflicting forces can result in severe engine damage beyond that of typical engine knock. LSPI is an issue unique to newer turbocharged and GDI engines and occurs under low-speed and high-torque conditions. However, a properly formulated motor oil can prevent its effects.

Key Updates

dexos1™: 2015

GM’s second-generation dexos1 specification is a global specification that aims to standardize the quality of oil installed in GM vehicles regardless of location. Similar to the GF-6 specification, dexos1: 2015 will address fuel economy and LSPI. It will also include new tests unique to GM focused on oxidative thickening, piston deposits, turbocharger deposits and wear control. It is due to be released in late August 2017.

  • Designed for 2011 model-year and newer engines
  • Targets higher levels of performance in all areas

NEW DEXOS1: 2015 & ILSAC GF-6 SPECIFICATIONS

  • Low speed pre-ignition protection preventing severe engine damage
  • Added piston deposit prevention for fuel economy and horsepower retention
  • Improved turbocharger protection to prevent turbocoking and increase longevity
  • Increased wear protection for maintaining like-new performance
  • Increased sludge protection for cleaner engines

ILSAC GF-6

Replacing the ILSAC GF-5 specification, the primary focus of ILSAC GF-6 will be increased fuel economy, oil robustness and protecting GDI and TGDI engines from LSPI and timing-chain wear. The spec will be split into GF-6A and GF- 6B to accommodate the trend toward lower-viscosity oils. GF-6B will provide a new category of oil designed for newer vehicles that require low hightemperature/high-shear (HTHS) and viscosities of 0W-20 or less. GF-6 is expected to be released in mid-2019.

  • GF-6A is designed for current modelyear engines and older requiring a traditional viscosity oil
  • GF-6B is designed for newer engines requiring lower viscosity oil

API/ILSAC

The International Lubricant Standardization Approval Committee (ILSAC) is a partnership between U.S. and Japanese automobile manufacturers. ILSAC and the American Petroleum Institute (API) work in tandem to develop engine protection standards and fuel economy requirements. Oils displaying the API Certification Mark, or “Starburst,” meet these requirements.

New Testing

As new requirements are revealed and the technology evolves, many standardized engine tests are being overhauled or replaced. GF-6 will feature at least six new engine tests while dexos1: 2015 will gain five. The tests encompass issues from low-temperature valvetrain wear (GF-6) to turbocharger deposits (dexos1: 2015).

AMSOIL Prepared for Change

AMSOIL Dealers can be well-assured that we will be ready for the implementation of the new specs with top-performing synthetic formulations. Details will be unveiled in upcoming issues of AMSOIL Magazine.