What should YOU look for when you are out looking for FUEL SAVING engine oil?

When you are going to look for FUEL Saving engine oil, you should always insist on:

ILSAC GF-5

API SERVICE SN

RESOURCE CONSERVING

ILSAC GF-5

ILSAC GF-5 lubricants are expected to improve passenger car performance from the sparkplug to the tailpipe. These performance improvements are good news for lubricant marketers, auto manufacturers, consumers, and the environment. 

New lubricants are already being designed to deliver improvements relative to ILSAC GF-4 in the following categories:

• Improved fuel economy and fuel economy retention 
• Engine oil robustness
• Protection of emission control systems 

Why GF-5?  

The Automotive Industry Speeds Towards GF-5

Emissions System Protection

The ILSAC GF-5 Needs Statement indicates the ILSAC GF-5 performance must provide improvements to ILSAC GF-4 in Emission System Durability.

For GF-5, Phosphorous has not been reduced from GF-4 (0.06% wt) due to potential wear concerns. As such, a minimum on Phosphorous content still exists.  Additionally, a Phosphorous Retention Test is to be incorporated into GF-5 with the objective of minimizing Phosphorous leaving the engine and entering the After-Treatment Devices (ATD). Previously, only a chemical limit was used.

A Phosphorous Retention Test will measure the amount of Phosphorous retained in the lubricant in the engine using the current Sequence IIIG engine test. Currently, ESCIT recommends to ILSAC using the Sequence IIIG @ 100 hours for this test.

High Phosphorous Retention oils will be beneficial for

• Extending the life of the ATD such as catalytic converters and oxygen sensors
• Improved Oxidation prevention to minimize oil thickening
• Improved protection against Copper and Lead corrosion
• Retention of the multifunctional benefits of the Zinc dialkydithiophosphate, or ZDP, such as anti-wear, anti-oxidant, anti-corrosion, and lowering the long term Tail-pipe NOx, CO, and HC emissions

Seal Compatibility

Seal compatibility performance is not new to lubricants.

OEMs have their own seal compatibility specifications for their factory fill and service oils, however there are GF-4 oils in the market today that do not meet the targeted seals compatibility performance.  OEMs are looking for a performance upgrade so that all oils meet the targeted elastomer compatibility performance.

In GF-5, the compilation of the OEM specs is now becoming a part of the ILSAC/API GF-5 specification. In addition, they are adding a new seal material commonly used by OEMs  

Oil leakage can result from a combination of chemical incompatibility between the oil; aging of the seal material and mechanical wear on the seal material.  By increasing the number of seal materials evaluated and a more stringent test, elastomer compatibility can be assured.

In addition preventing oil leaks is good for the environment and it keeps the oil where it is needed most - in the engines lubrication system.

The new performance requirement of Seal Compatibility will have a measurable impact on the formulating challenge of GF-5.

Fuel Economy

The ILSAC GF-5 Needs Statement indicates the ILSAC GF-5 performance must provide improvements to ILSAC GF-4 in fuel economy and fuel economy retention.

Previously in GF-2 and GF-1, the Sequence VIA test was used and it evaluated only fresh oil fuel economy. In GF-3, the Sequence VIB test was used and it measured fuel economy on both fresh and aged oil and also in GF-4. Fuel economy deteriorates over time, which is why aged oil is also measured in the Sequence VIB.

The industry decided a more modern engine representative of today's technology is required for GF-5, and so the GM High Feature 3.6 liter engine will be used. The fuel economy test will be identified as the Sequence VID engine test. Previously, the Sequence VIB test used a Ford 4.6 liter V-8 engine. The more modern V-6 engine is desired to improve the precision of the fuel economy test

Congress has passed legislation mandating CAFÉ requirements to be set at 35 mpg by the year 2020. The auto industry is under tremendous pressure to increase MPG and will look to the Oil and Additives industries to help achieve this goal.

E-85 Rust Protection (Rust protection when using Biofuel)

Many vehicles will be built to be flexible fuel vehicles. They will be capable of running on conventional unleaded regular gasoline; on E85 which is 85 % Ethanol plus 15 % conventional unleaded gasoline; or on any mixture in between.

Although very few vehicles will actually run on E85 the majority of the time, the OEMs want to ensure they do not have detrimental performance when using E85. The two areas of concern are rust protection and emulsion retention.

A bench test has been added to GF-5 to ensure sufficient protection from rust caused by biofuels such as E-85 fuel in Flexible Fuel Vehicles

Biofuels such as E-85 are different from gasoline and may cause engine rust to occur in Flexible Fuel Vehicles, so it is important that the new GF-5 formulations are fortified to prevent rust. Biofuels such as E-85 are coming into wider use and GF-5 oils must be able to address this potential rust issue.

The new performance requirement of E-85 rust protection has a measurable impact on the formulating challenges of GF-5.  

E-85 Emulsion Retention

Many vehicles will be built to be flexible fuel vehicles. They will be capable of running on conventional unleaded regular gasoline; on E85, which is 85% Ethanol plus 15% conventional unleaded gasoline; or on any mixture in between.

Although very few vehicles will actually run on E85 the majority of the time, the OEMs want to ensure they do not have detrimental performance when using E85. The two areas of concern are emulsion retention and rust protection.

An emulsion retention test is to be included in GF-5 to ensure emulsion retention occurs when biofuels such as E85 are used in FFV.

The byproducts of combustion of biofuels such as E85 fuel are water and acids that tend to be very corrosive if not controlled. The retention of the E-85 emulsion is necessary as it helps to minimize the corrosivity that the water and acids from combustion and condensation may cause.

The new performance requirement of E85 Emulsion Retention have a measurable impact on the formulating challenges of GF-5.

5W-XX Volatility

Controlling oil consumption (keeping oil in the engine) is necessary to ensure proper engine performance and oil consumption is related to oil volatility. The GF-5 standard for oil volatility remains at the GF-4 level of 15% maximum. Oils wanting the ILSAC Specification must meet this volatility requirement.

Other factors influencing oil consumption include engine age, engine design, and proper maintenance.

Oil volatility is directly related to the selection of proper base oil components and not additives.

Engine Sludge Protection

The Sequence VG test evaluates the lubricant's ability to prevent sludge and varnish formation. The Sequence VG test simulates moderate temperature taxicab service, urban and suburban delivery service, or commuting back and forth to your job. Sludge leads to deposit buildup in the engine and can lead to engine failure. The Sequence VG test also looks at piston deposits and oil screen plugging from sludge.

For GF-5, Engine Sludge Protection will be measured by the Sequence VG test, which is the same test used in GF-4. Currently under discussion between ILSAC and OIL are Average Engine Sludge, Average Rocker Cover Sludge, and Oil Screen Clogging performance for GF-5 compared to existing limits on GF-4.

OEMs want to see improvements in oil screen sludge for GF-5 to prevent the engine from lubricant starvation. The industry is investigating the accuracy of the measuring technique to determine if a change in procedure is possible.   

Dispersants are used to control the formation of sludge but negatively impact fuel economy.  

Piston Cleanliness

The ILSAC GF-5 Needs Statement indicates that the ILSAC GF-5 performance must provide improvements to ILSAC GF-4 in Engine Oil Robustness, which includes Piston Cleanliness along with  Engine Sludge Protection, and Turbocharger Protection.

A piston cleanliness test is required as piston deposits can get behind and around the piston rings, which can cause the rings to stick and be sluggish.  As a result, the deposits in the ring area displace gas which is required for ring pressurization. When deposits get behind and around piston rings, a lack of compression occurs. This usually results in increased emissions, decreased fuel economy, and decreased performance.

A piston cleanliness test is also required because deposits can build on the piston crown causing pre ignition. Deposits can also build up on the piston undercrown, which increases piston temperature.  Both can result in decreased performance.

To address this issue, the Sequence IIIG engine test was developed to evaluate high temperature deposits. The Sequence IIIG test is an oil thickening and piston deposit test run under high-temperature/high load conditions. This test also provides information about valve train wear. The test simulates high-speed service under relatively high temperature conditions.

Piston Cleanliness is measured by the weighted piston deposit rating in the Sequence IIIG test. Currently under discussion between ILSAC and OIL is the minimum average weighted piston deposit rating for GF-5 compared to the existing GF-4 specification.

Detergents are used to prevent piston deposit build-up, but trade off exists between increased Piston Cleanliness and Fuel Economy. The detergent components that go the metal surfaces to keep the engine's parts clean compete against the friction modifier components that go to the metal surfaces to reduce friction and improve fuel economy. 

Turbocharger Protection

Use of the TEOST 33C deposit bench test is being considered in GF-5 to evaluate Turbocharger Protection.

During this test, problems were observed with oxidative degradation/thermal coking of engine oil in the turbocharger bearing area during hot shut-down. It is necessary to protect the bearing from deposits because deposit build-up in the turbocharger bearing area can lead to loss of engine performance and possibly engine failure.

Turbocharger Protection is important, but there are tradeoffs when it comes to Fuel Economy. The detergent and dispersant components that go the metal surfaces to keep the engine's parts clean and prevent deposit build-up in the turbocharger, compete against the friction modifier components that go to the metal surfaces to reduce friction and improve fuel economy.

It is estimated that 15 to 25% of all Ford, GM and Chrysler engines by Model Year 2011 will have turbochargers.

Oxidative Thickening

Oil oxidation leads to oil thickening and potential pumpability problems. Think about pumping water vs. honey. As oil oxidizes it gets more viscous and can negatively impact fuel economy.  In addition, oil oxidation makes it difficult for the oil to circulate through the lubricating passages of the engine and may lead to oil starvation. Oil starvation can result in engine failure.

To address oxidative thickening, the Sequence IIIG test is used which is the same test used in GF-4. The Sequence IIIG is more severe than the previous Sequence IIIE and IIIF as the engine test is hotter and longer to simulate modern engines.

No differences in oxidative thickening limits will exist between GF-5 and GF-4. The formulating challenge will be to prevent oxidative thickening while not negatively affecting Fuel Economy or Engine Oil Robustness.

Wear Protection

Zinc Dialkydithiophosphate, commonly referred to as ZDP, is a classic and proven component for wear protection.

Existing technology is available to address the wear protection needs of GF-5, however many of the additives used to inhibit wear contain Phosphorous. Phosphorous in the exhaust gas has been shown to harm after-treatment devices.

The engine lubricant must protect from premature wear. The Sequence IVA is a flat follower valve train wear test and has proven to be adequate.