. Thanks for the responses.
Safe difference?
Thread Starter
Team Owner
Joined: Jul 2016
Posts: 25,303
Likes: 1,683
From: The Steel City, Colorful Colorado
Winner 2020 C7 of the Year - Modified
Safe difference?
Getting ready to do an oil change with Mobile 1 5W-30 Advanced Full Synthetic and just noticed that my 5 quart jug says dexos Gen2 and my quart sizes just say dexos. Is there any issue or difference if I mix a dexos with dexos Gen2 oil?
Race Director
Joined: Apr 2017
Posts: 10,247
Likes: 888
From: Hickory NC
2025 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
2020 C5 of the Year Finalist - Modified
St. Jude Donor '17 thru '26
According to the National Oil & Lube News:
Dexos1 Gen 2
The most current dexos1 specification (dexos1 Gen 2) was released in 2015 to provide even higher engine performance and protection, particularly low speed pre-ignition (LSPI) protection in small displacement turbo-charged engines.
GM has developed four new engine tests for this updated specification:
For more information about dexos1 Gen 2, visit: www.centerforqa.com/dexos/
So, is it better than the original Dexos ? Probably. However comments in other writings on the new generation Dexos speak more to the small, turbo engines, as briefly mentioned above.
Additionally, ACDelco Techconnect says:
“Since dexos1 Gen 2 is fully backwards compatible with all pre-2018 model GM vehicles, the previous generation of dexos1 generation will no longer be produced after this full transition.” Nothing there indicating any incompatibility between the two oils; just one has been improved.
Guess if you mix it, you will have Dexos1 Gen 1.5
Dexos1 Gen 2
The most current dexos1 specification (dexos1 Gen 2) was released in 2015 to provide even higher engine performance and protection, particularly low speed pre-ignition (LSPI) protection in small displacement turbo-charged engines.
GM has developed four new engine tests for this updated specification:
- New General Motors Oxidation & Deposit Test (GMOD) verifies the improved oxidation and deposit control characteristics.
- New Stochastic Pre-ignition Test verifies the added protection for turbocharged engines and pre-ignition concerns.
- New Turbocharger Deposit Test verifies the added protection for turbocharged engines and minimizes deposit formation, which ensures optimal performance during engine life.
- New Aeration Test (bubble control) ensures the air bubbles in the oil dissipate quickly to improve oil performance.
For more information about dexos1 Gen 2, visit: www.centerforqa.com/dexos/
So, is it better than the original Dexos ? Probably. However comments in other writings on the new generation Dexos speak more to the small, turbo engines, as briefly mentioned above.
Additionally, ACDelco Techconnect says:
“Since dexos1 Gen 2 is fully backwards compatible with all pre-2018 model GM vehicles, the previous generation of dexos1 generation will no longer be produced after this full transition.” Nothing there indicating any incompatibility between the two oils; just one has been improved.
Guess if you mix it, you will have Dexos1 Gen 1.5
Administrator
Joined: Mar 2001
Posts: 368,390
Likes: 24,795
From: In a parallel universe. Currently own 2014 Stingray Coupe.
C7 of the Year - Modified Finalist 2021
MO Events Coordinator
St. Jude Co-Organizer
St. Jude Donor '03 thru '26
NCM Sinkhole Donor
CI 5, 8 & 11 Veteran
You will be fine mixing the two. 
Last edited by Vetteman Jack; Jun 23, 2018 at 11:20 PM.
Thread Starter
Team Owner
Joined: Jul 2016
Posts: 25,303
Likes: 1,683
From: The Steel City, Colorful Colorado
Winner 2020 C7 of the Year - Modified
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Drifting
Joined: Mar 2013
Posts: 1,496
Likes: 355
From: Little Rock Arkansas
^^^ Yeah you'll be fine. The Dexos 2 standards have in a way superseded Dexos primarily as mentioned to address requirements of smaller gasoline engines. Your older Dexos 5w-30 will function in the same way as Dexos 2 5w-30.
Going forward you're likely not going to find in stores Dexos standard oil since Dexos 2 has replaced it. Unless you have some sort of power adders and/or accompanying modifications that necessitates running a different type oil for whatever reason your C5 is well within Dexos 2.
Going forward you're likely not going to find in stores Dexos standard oil since Dexos 2 has replaced it. Unless you have some sort of power adders and/or accompanying modifications that necessitates running a different type oil for whatever reason your C5 is well within Dexos 2.