Latest Dexos Generation Gains Steam


Latest Dexos Generation Gains Steam
A mechanic working in a Chevrolet dealership checks a car's oil. © Phoutthavong SOUVANNACHAK

Seven months after its commercial launch, General Motors says it is pleased with the uptake of its latest engine oil specification for gasoline-powered vehicles – Dexos 1 Gen 3 – which is on a trajectory similar to that of its predecessor spec.

GM has already begun work on the next spec and is also developing proprietary standards for lubricants and fluids used in electric vehicles, an official with the automaker said.

GM still participates in the International Lubricant Standardization and Advisory Committee, a trade group of American and Japanese automakers that develops industry engine oil specifications, but it has been developing its own standards and recommending them in its own vehicles since 2009. GM has two series of oil standards – Dexos 1 for oils used in gasoline-powered vehicles and Dexos 2 for those used in light-duty vehicles running on diesel.

Dexos 1 Gen 3 is the third generation of Dexos 1 and replaces Dexos 1 Gen 2. GM published the new spec in March of 2021 and began recommending it in vehicles last September. The company plans to update its website for the program this month to show that 168 products have been licensed for meeting the spec, according to Nathan Siebert, engineering manager at GM for fluids and lubricants.

“GM has an aggressive roll out timing, and we are pleased with the continued pace of the licenses’ approvals,” Siebert told Lubes’n’Greases last week. “Of course, we would like to see all oils carry the Dexos quality seal, but we feel the number of Gen 3 approvals will be similar to that of Gen 2.”

Marketers of oils with Dexos 1 Gen 2 licenses are still permitted to display the Dexos trademark and promote products as meeting that spec. The company has not set a date for halting Gen 2 approvals, but all products promoted as being Dexos certified will be required to be licensed for Gen 3 beginning with sales occurring on Sept. 1 of this year.

Siebert said Dexos 1 Gen 3 differs from Gen 2 in several respects. It includes tests incorporated into ILSAC GF-6, the latest ILSAC category for light-duty engine oils, which came to market in 2020, and is also updated to accommodate the latest ACEA standards from the European Automobile Manufacturers Association. Dexos is a global program, and GM incorporates requirements of ILSAC, ACEA and American Petroleum Institute specs and then adds additional requirements of its own.

Dexos 1 Gen 3 also includes a new fuel economy test based on the Chevrolet Silverado as well as a new test that GM developed to gauge an oil’s ability to prevent low-speed pre-ignition. The latter test is an overhaul of a previous version, incorporating a new drive cycle and a new fuel type.

While licensing oils that have passed requirements of the new specification, the automaker has also begun developing the standard that will follow it.

“GM is targeting the 2027 timeframe for a Gen 4 engine oil specification that will be centered around improved fuel economy, SPI, wear and oxidation improvements, as well as addressing any updates there may be to emissions requirements,” Siebert said.

He added that the company has also begun developing standards for lubricants and fluids that will be used in EVs, but he declined to elaborate.