GM Dexos Engine Oil Specifications

Dexos is an engine oil quality standard developed by General Motors (GM) that defines the technical requirements an oil must meet to ensure improved engine protection, cleanliness, and fuel efficiency.

Engine oils approved under the General Motors Dexos specification are recommended for use in all GM vehicles, except those equipped with Duramax diesel engines, which require oil meeting the API CJ-4 quality standard.

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

Dexos1 ™ Gen 1
Dexos® oils are made with synthetics or synthetic blends only.
Improved antioxidant technology that keeps the oil from oxidizing. Dexos® oil drain intervals are typically up to 15,000 miles. Lower viscosity that resists engine burn and heat better and longer than other oils on the market.

Dexos1 ™ Gen 2
General Motors' new generation of dexos1 ACDelco dexos1 Gen 2 Full Synthetic! It is designed to meet the lubrication needs of today's smaller, higher performance engines. This new fully synthetic system replaces the dexos1 Gen 1 synthetic blend specification.

All GM engine oils will transition to this new formulation in 2017. Since dexos1 Gen 2 is fully backward compatible with all pre-2018 GM models, the first generation dexos 1 oil will no longer be produced after the full transition.

Benefits of Dexos1 Gen 2 fully synthetic engine oils:
• Helps maintain maximum fuel economy
• Reduces sludge and improves engine cleanliness
• Significantly reduces low-speed pre-ignition
• Provides superior wear protection
• Reduces turbocharger slag
• Improves oxidation control.

Dexos1 Gen 3
GM Dexos 1 Gen 2 update. Dexos 1 Gen 3 is scheduled to be released on September 1, 2021.
Gen3 is a synthetic engine oil that meets General Motors’ latest engine oil specification, dexos1 Gen3. It is designed for modern gasoline engines, providing excellent protection against wear, deposits, and contaminants, strong cold-start performance, and helping to maintain low fuel consumption. Dexos1 Gen3 oils meet or exceed the API SP and ILSAC GF-6 standards, are backward compatible with previous dexos1 requirements, and help ensure long engine life and cleanliness.

GM Dexos 2
The GM Dexos 2 specification is intended to replace both the GM-LL-A-025 (gasoline) and GM-LL-B-025 (diesel) specifications in the European market. GM Dexos 2 compliant oils are required for vehicles manufactured from 2011, 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 deposit formation test and the low-temperature sludge accumulation test.

GM-LL-A-025
Special GM approval for long-life engine oil for gasoline engines. Viscosity is SAE 0W-30. The product meets ACEA A3 / B3. Oil change intervals can be up to 30,000 km. Recommended for vehicles built before 2011.

GM-LL-B-025
Special GM approval for long-life engine oil for diesel engines. Viscosity is SAE 5W-40. The product meets ACEA A3 / B3 / B4. The oil change interval can be up to 50,000 km. Recommended for vehicles built before 2011.
 

General Motors Dexos automatic transmission fluids

Dexron Type A, suffix A
The specification was established in 1957. It requires the oil to meet certain kinematic viscosity limits.

Dexron IID
General Motors Dexron®-IID specification. ATF was issued in 1975. Included ATF coolant corrosion requirements not listed in the Dexron®-II list.

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

Dexron IIIF
General Motors automatic transmission fluid specification introduced in 1994. Successor to Dexron IID and IIE.

Dexron IIIG
Successor to Dexron IIIF automatic transmission fluid. It has the same low temperature properties as Dexron IIE, but with antioxidant and friction material modifications. Introduced in 1997.

Dexron IIIH
Dexron III License H was introduced in June 2003 to replace Dexron III G fluid. It has an oxidatively stable base oil (Group 2 or Group 3). According to this specification, oils have longer friction and anti-shrinkage properties, better foam control and longer fluid life.

Dexron VI
The specification was introduced in 2005 to replace Dexron IIIH. This specification requires better properties, oxidative stability and anti-foam properties. Oils meeting this specification can be used with longer oil change intervals and are energy-efficient.

Dexron HP
2013 and later GM 8L90 8-speed RWD automatic transmissions

• History: When GM introduced its 8-speed automatic transmissions (8L90), they created a new oil standard called Dexron HP (High Performance).
• Problem: A few years later, it became clear that the original fluid was too hygroscopic (it absorbed moisture). The moisture altered the fluid’s properties, causing slipping of the torque converter clutch plates and resulting in noticeable vibrations or “shudder” during driving.

Dexron LV ATF HP
On October 1, 2018, a special fluid specification (GMNA-9986555 [27]) was introduced for a revised "Dexron Approved" Mobil 1 Synthetic LV ATF HP. This revised fluid was introduced in December 2018 in GM Technical Service Bulletin 18-NA-355. The change is intended to help improve torque converter clutch judder in GM 8L90 and 8L45 automatic transmissions after a full system flush.

• Solution: GM and Mobil developed a new fluid with an improved chemical formulation.
• Name change: To distinguish it from the older fluid with the “faulty formulation,” it began to be labeled on bottles as Mobil 1 LV ATF HP (LV = Low Viscosity), and the bottle label was changed to blue (known as the Blue Label).
• Backward compatibility: This newer fluid (2018+) fully replaces the older fluid (2013).

DEXRON ULV
2017 and later GM 10L90 10-speed automatic transmissions


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