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Next Oil Standard: GF5, and GM Dexos

Bruce Nunnally

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Interesting article here: http://www.asashop.org/autoinc/nov2009/cover.htm


While the GF-4 standard was acceptable when it was introduced nearly six years ago, new formulas will be required to meet upcoming government regulations for improved fuel economy and lower emissions. Improvements over GF-4 must include:

* Fuel economy and fuel economy retention

* Engine oil robustness

* Protection of emission control systems

The next ILSAC standard, GF-5, is scheduled to be released next year, about the time the 2011 models hit the market. The challenges toward attaining GF-5 are many. More sophisticated additive mixtures will need to be incorporated for improved:

* Fuel economy

* Emission systems protection

* Rust protection with the use of E85 (ethanol/gasoline blend)

* Protection for turbochargers

* Avoiding engine sludge

* Keeping pistons clean

* Compatibility with sealing materials

Right now, oil formulators are performing six months of testing to ensure their products meet the stringent GF-5 standards. After the testing has been completed and the results examined, API will begin licensing marketers to produce and distribute GF-5 certified products. The product range is expected to include 0W-20, 0W-30, 5W-20, 5W-30 and 10W-30.

While each company must meet the stringent GF-5 standards, they may take slightly different approaches to meeting the specification in types and amounts of additives and modifiers. One thing is certain: there will be a higher content of additives and synthetic compounds. This will increase oil life, protect the metal and sealing materials better, but increase the cost of the end product. The end price of GF-5 may range from 15 percent to 20 percent higher than the current GF-4 spec, due to the formulation, development, testing, royalties and marketing costs.

GM Dexos


General Motors Corp. has decided to take a separate path to setting standards for its global family of engines. The company plans to introduce its Dexos global motor oil specification (until recently called Global Engine Oil Specification, or GEOS) with 2011 models. Actually, the standard contains two specifications: Dexos-1, as factory-fill and service-fill for gasoline engines; and Dexos-2 as factory-fill and service-fill for diesel engines. Of course, both are compatible with previous models.

GM currently manufactures more than 20 engines in 18 plants worldwide and assembles vehicles in 37 countries - although all that may change drastically under the new government-controlled strategy. The intent of the global Dexos specification is to ensure the same quality and specification from all suppliers for all engines in all countries.

According to Eric Johnson, of GM Powertrain, the reasons for developing the Dexos specifications are:

* To ensure worldwide availability of equal quality oil for factory and service fill.

* To further improve fuel economy.

* To provide a more robust formulation (added engine protection).

* To further extend service intervals.

* To support longer intervals for GM's Oil Life Monitoring System (OLMS).

This graphic illustrates expected oil change intervals under the current ILSAC GF-4 standard. The intervals are expected to rise significantly under GF-5. Image courtesy of GM.

This graphic illustrates expected oil change intervals under the current ILSAC GF-4 standard. The intervals are expected to rise significantly under GF-5. Image courtesy of GM.

GM has used OLMS for many years and it is now entering a completely global application. These intervals, based on engine speed, ambient air and engine temperatures, runtime, etc., will certainly lengthen with the new specification. "We're always trying to calibrate OLMS to maximize drain intervals to reduce the nation's dependence on crude oil," Johnson said. "It's about putting the customer first and continuing GM's commitment to quality, design and innovation."

Dexos-1, for gasoline engines, will be offered in these formulations: 0W-20, 5W-20, 0W-30 and 5W-30. Dexos-2, for light diesel engines, will be packaged in 5W-30, 0W-40 and 5W-40.

Dexos-1 will supersede the current GM6094M specification for most GM gasoline vehicles. At this time, GM plans to also use Dexos-1 to replace the GM4718M spec for Corvette, Cadillac and engines with turbochargers, which stipulated Class III synthetic blends; Mobil 1 or the equivalent.

READ MORE: http://www.asashop.org/autoinc/nov2009/cover.htm


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Sounds like it's all Mobil 1 or the equivalent now.

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