General Motors oil specifications

Engine oils for Chevrolet, Buick, GMC, Cadillac, Holden, Oldsmobile, Pontiac, Hummer, Saturn, Asüna, Acadian, Alpheon, Geo are approved by General Motors.

General Motors approvals

General Motors Corporation initially issued certificates for its vehicles coded GM-LL, followed by the letter A or B (A for petrol engines and B for diesel engines), similar to the ACEA classification until 2004. And since 2011, new engine oil quality standards have been introduced for different markets: Dexos-1 for the American market and Dexos2 for the European market.

GM Oil Specifications

General Motors is the largest American car corporation, and for 77 years the world’s largest car manufacturer until 2008. Based on January-April 2018 sales, the group ranks fifth in the global automotive manufacturer ranking.

Engine oils with the GM Dexos specification are used in all GM engines except the Duramax diesel engines, which require oils with API CJ-4 approval. Having a proprietary oil classification makes it easier to choose an engine oil for General Motors vehicles.

Developed in 2006 and patented worldwide in 2007, the General Motors (GM) specification is called dexos™. It is divided into dexos1™ for petrol engines and dexos2™ for light duty diesel engines.

What is the General Motors specification?

General Motors specifications are symbolic designations of engine oil properties for a specific type of General Motors vehicle, and it is by these that you select the oil for your General Motors vehicle. By choosing an oil to the appropriate specification, you ensure that you are using the correct oil for your General Motors vehicle.

Oil Specifications GM

General Motors engine oil approvals

The main viscosity for GM dexos1™ and dexos2™ factory and service oils is 5W-30. To meet dexos1™ requirements, engine oils must be either fully synthetic or a blend of synthetics.

GM dexos approved oils are recommended for use in all GM vehicles except those with Duramax diesel engines which require API CJ-4 quality oil.

GM Dexos 1

Designed to suit GM Dexos 1 gasoline engines, it replaces the GM-LL-A-025, GM6094M and GM4718M specifications. This specification is generally recommended for GM vehicles manufactured for the North American and Asian markets. Compared to ILSAC GF-5 it has more stringent requirements for piston deposit formation, aeration, oxidative stability, wear, low temperature pumpability and volatility.

GM Dexos 2

The GM Dexos 2 specification is intended to replace the GM-LL-A-025 (petrol) and GM-LL-B-025 (diesel) specifications for the European market. Oils conforming to GM Dexos 2 are required for vehicles manufactured from 2011 onwards, but are also compatible with older models. This specification is based on the ACEA C3 standard, but also includes elements of the ILSAC GF-4 fouling and low temperature sludge test.

Technical data of Legacy engine oil


Special GM approval for long-life engine oil for petrol engines. The viscosity is SAE 0W-30. The product meets the requirements of ACEA A3/B3. The replacement interval can be up to 30,000 km. Recommended for vehicles produced before 2011.


Special GM approval for long-life engine oil for diesel engines. The viscosity is SAE 5W-40. Product complies with ACEA A3/B3/B4. The oil change interval can be up to 50,000 km. Recommended for vehicles produced before 2011.

Fluids for automatic transmissions

Dexron Type A, Suffix A

A specification introduced in 1957. It requires that the oil meets certain kinematic viscosity limits.

Dexron IID

General Motors Dexron®-IID specification. ATF issued in 1975. Contained ATF coolant corrosion requirements not specified in Dexron® – II.

Dexron IIE

General Motors Dexron®-IIE specification. ATF released in 1991 requiring improved low temperature performance over Dexron®-IID, 20,000 cP at minus 40 °C.

Dexron IIIF

GM specification for automatic transmission oil introduced in 1994. Successor to Dexron IID and IIE.

Dexron IIIG

The successor to Dexron III(F) automatic transmission fluid. Has the same low temperature characteristics as Dexron IIE but with changes in antioxidant and friction materials. Introduced in 1997.

Dexron IIIH

Dexron III Licence H was introduced in June 2003 to replace Dexron III G fluid. It has an oxidation-stable base oil (group 2 or group 3). Oils to this specification have longer retention of friction and anti-seize properties, better foam control and longer fluid life.

Dexron VI

This specification was introduced in 2005 to replace Dexron IIIH. This specification calls for better properties, oxidation stability and anti-foam performance. Oils meeting this specification can be used with extended drain intervals and are energy efficient.


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