[redwngr]

According to the 3.0L supplemental manual, 0W-20 to the DexosD spec is what you're looking for.

Fwiw, it's not the same oil as used/recommended the 6.6L.

Currently there are only 2 oils that been approved:

ACDelco Light Duty Diesel General Motors dexosD™ 0W-20 DD0751IA015 Global
Mobil Super 3000 XE2 ExxonMobil Oil Corp. dexosD™ 0W-20 DD0752IA015 Global

Link : dexos®


..

 

[redwngr]

https://www.mobil.com/en-US/Passenger-Vehicle-Lube/pds/GL-XX-Mobil-1-ESP-x2-0W20

 

[redwngr]

dexos® Licensed brands | General Motors

Licensed dexos®D brands

Brand Name	Supplier	Specification	Viscosity	License Number	Region
ACDelco Light Duty Diesel	General Motors	dexosD™	0W-20	DD0751IA015	Global
Mobil Super 3000 XE2	ExxonMobil Oil Corp.	dexosD™	0W-20	DD0752IA015	Global

They have the same license number.

(My dealer says mobil is the current supplier for all GM engine oils)

If you look at the pages for Dexos1Gen3 (the gas engine oil) and Dexos2 (the diesel oil for 2.8L dmax) there are many licences.

The Dexos2 and DexosD oils are NOT recommended for the 6.6L dmax.

 

[redwngr]

If you get the 2021 diesel supplements for the canyon/colorado 2.8, the half ton 3.0 and the HD 6.6 you will find that each one has a different oil spec recommendation.

Must be a reason.

 

[redwngr]

From dexos® Licensed brands | General Motors

Brand Name	Supplier	Specification	Viscosity	License Number	Region
ACDelco Light Duty Diesel	General Motors	dexosD™	0W-20	DD0751IA015	Global
Mobil Super 3000 XE2	ExxonMobil Oil Corp.	dexosD™	0W-20	DD0752IA015	Global

 

[redwngr]

Amsoil 0w20 is approved.

Waiting on PPE filter and insane diesel bypass after the first oil change

Only by amsoil....

 

[redwngr]

I don't know the reason, but GM is currently selling 3 dmax engines.

2.8L 4 cyl
3.0L 6 cyl
6.6L 8 cyl

They recommend a different oil specification for each one.

 

[redwngr]

I am waiting to place an order for the 2022 3L Duramax.
Yesterday I was at Costco here in Alberta and noticed a box (2pack) of 0W-20 oil that was open so I pulled the jug out and it had the Dexos 2 symbol on it and showed approved. Check it out for yourself?

Dexos2 0w-20 is not the same as DexosD 0w-20

Dexos2 oils are used in the 2.8L duramax

The 6.6L uses CK-4 or CJ-4 15w-40.


Yupp, three different dmax diesels with
-- three different oil specifications recommendations
-- three different oil viscosity recommendations

 

[redwngr]

dexos® Licensed brands | General Motors

There are now 3 oils on the dexosD approved list.

Dexos2 has several pages of approved oils.

Dexos1 Gen2 (gas engines) has many pages of approved.

Apparently they now also have a Dexos1 Gen3 spec for gas engines. Only 9 or 10 on it so far.