dexos™1 Gen 3 is the latest generation of GM-certified engine oil. The recently introduced engine oil specification addresses the challenge of meeting the needs of new engine hardware — in particular, higher power density engines equipped with new technologies — with enhanced oxidation, turbocharger protection and engine cleanliness.
The dexos1 Gen 3 specification (Fig. 3) is the new requirement for factory fill and service fill for gasoline engines, replacing the previous dexos1 Gen 2 specification. It’s backward compatible with all previous generations of dexos1.
Fig. 3
dexos1 Gen 3 is currently available in 0W-20 and 5W-30 viscosity grades. Refer to the electronic parts catalog or acdelco.com for the most up-to-date applications and a complete list of engine oils.
TIP: Viscosity recommendations vary according to temperature and engine manufacturer, so using the right viscosity grade oil is critical for proper engine performance. Always check the appropriate vehicle owner manual for the proper viscosity grade for the vehicle being serviced.
dexos1 Gen 3 features:
- High resistance to oxidation, keeping the oil from breaking down, to provide enhanced turbocharger protection and engine cleanliness
- Fuel savings and prolonged engine life by fighting wear and reducing friction
- Easier starts and better engine protection in cold weather, stop-and-go driving and towing heavy loads
- Cleaner engine operation by resisting varnish and sludge that can affect performance along with upgraded performance limits for deposit and sludge tests
Next Generation
The dexos1 specification, introduced in 2010, was designed to further improve fuel economy and fuel economy retention, which allows the oil to maintain its fuel economy benefits throughout the life of the oil, while also providing a more robust formulation for added engine protection and aeration performance. The enhanced specification also supports GM’s Engine Oil Life System (EOLS), minimizing the use of engine oil, and reduces the duplication of requirements for a large number of internal GM engine oil specifications.
In addition to the new dexos1 Gen 3 specification, the International Lubricants Standardization and Approval Committee (ILSAC) recently introduced the GF-6 engine oil performance standard, which aims at meeting changing industry demands of improved fuel economy and engine protection.
Most of the dexos1 Gen 3 tests have significantly higher limits than ILSAC GF-6. In addition, dexos1 Gen 3 has its own specified engine tests to evaluate low-speed pre-ignition mitigation, fuel efficiency, oxidation, and turbocharger deposit performance and wear protection.
Along with the GF-6 tests, many Gen 2 tests are carried over to Gen 3, including a test for turbocharger deposits at tighter limits. Gen 3 also includes an updated stochastic pre-ignition (SPI) test, compared to the limits for Gen 2, as well as a new fuel efficiency test. (Fig. 4) In addition, the specification has eliminated most European tests.
Fig. 4
dexos1 Gen 3 Availability
The newly formulated dexos1 Gen 3 product is now available in bulk through the GM Oil Program. The transition from the current dexos1 Gen 2 to Gen 3 will be a running change and as the old product is sold down, new product will be supplied. Pricing for both formulations is the same.
For additional program details, refer to GlobalConnect message GCUS-9-12087 (U.S.) or Bulletin GMP2021-276 (Canada).
– Thanks to Ashwin Medhekar and Kim Bennett
