2022 GMC Sierra 3.0 Duramax Amsoil 0w20 6500 miles UOA

[dedonderosa]

Hey everyone just posting this up for my good buddy who just had his first UOA done on his 2022 3.0 Duramax. 6500 miles on oil. Amsoil 0w20 Diesel oil meeting dexos D. Spec. Just wanted to get some others opinions on this analysis and if you have any other recommendations on oil for this truck. Thanks

Truck 2022 Sierra 3.0 Duramax w/24,500 miles
Oil Amsoil 0w20 diesel 6500 miles on oil

 

[Danno]

Some fuel dilution noted, if BS test to be trusted.
Interesting that Amsoil states : Use in any applications that require .... dexosD certification, but that cert is not showing on the bottle label nor does it say the oil is certified as "dexosD".

https://amsoilcontent.com/ams/lit/databulletins/g3713.pdf

I find this word salad stuff annoying.

 

[addyguy]

Weak sauce, wear seems high. I know there is stuff ‘we can’t see’; but additive treat rates seem really low even for a modern diesel.

 

[burbguy82]

I dont see the point of using Amsoil, unless you use the signature series. Wow, 0w20 for a diesel truck. What a world we live in these days.

 

[Thermo1223]

Stop using Blackstone for one and I would use a 0w30 IMO. I can certainly trust 0w20 in a gasser but diesel...

 

[Invisible]

@High Performance Lubricants has a DexosD 0W-20 oil. I would use and trust that one. Alternatively, Mobil 1 ESP X2 0W-20 is in fact DexosD licensed.

You can order the HPL 0W-20 DexosD here: https://www.advlubrication.com/coll...ssenger-car-engine-oil?variant=47737533595841

HPL uses a Dexos D additive package, not a "compatible" additive package. There is a difference between the two.

Make sure to select 0W-20 D:

 

[Pablo]

@High Performance Lubricants has a DexosD 0W-20 oil. I would use and trust that one.

HPL uses a Dexos D additive package, not a "compatible" additive package. There is a difference between the two.

First line - Why?

Second line - explain the difference, in detail and why you wrote that.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

I thought a single UOA was not used to choose a motor oil, or proclaim "weak sauce".

Interesting!
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Yeah, SAE 20 vis range and diesel engines. Not sure.

 

[Invisible]

First line - Why?

Second line - explain the difference, in detail and why you wrote that.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

I thought a single UOA was not used to choose a motor oil, or proclaim "weak sauce".

Interesting!
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Yeah, SAE 20 vis range and diesel engines. Not sure.

The recommended oil for the Duramax 3.0 Diesel engine is Mobil 1 ESP X2 0W-20. I would trust HPL 0W-20 DexosD over the Mobil 1, since the HPL is blended with PAO+Star Polymers, so shearing isn't an issue. My comment was not aimed at AMSOIL, though I should have worded it better.

As to 0W-20 not belonging in a Diesel engine, I agree. AMSOIL makes a 5W-30 DexosD, so I would definitively use that instead of the 0W-20. Either that engine has some beefy rod bearings, or GM is chancing it to make it out of warranty without grenading itself.

 

[fantastic]

You're below average but that is quite some Fe. I'd be curious if this engine was actually built around a 20 grade or if it was back spec'd from a higher visc. Namely I thought this engine might be used elsewhere in the world. I wonder what the manual says.

 

[MrHorspwer]

You're below average but that is quite some Fe. I'd be curious if this engine was actually built around a 20 grade or if it was back spec'd from a higher visc. Namely I thought this engine might be used elsewhere in the world. I wonder what the manual says.

The 3.0L diesel is only used in full size trucks and SUV produced in North America. Along with the North American market, it is also exported to South America and Australia.

The engine launched in 2019 and 0W20 DexosD has been the recommend spec and viscosity for all sales regions (per the localized owners manuals) since the launch.

At launch, the engine was RPO LM2. In 2023, it transitioned to RPO LZ0. One of the big changes between LM2 and LZ0 is that LZ0 has steel pistons, where LM2 has aluminum.

My first thought about extra wear Fe would be the steel pistons, but with the OP's truck being a 2022, it is an LM2 with aluminum pistons.

 

[Danno]

At launch, the engine was RPO LM2. In 2023, it transitioned to RPO LZ0. One of the big changes between LM2 and LZ0 is that LZ0 has steel pistons, where LM2 has aluminum.

I wonder why the switch, were the aluminum pistons having durability issues?
Did they keep the belt driven oil pump?

 

[burbguy82]

why is this on the gasser forum?

 

[dedonderosa]

can someone please move this thread to the diesel UOA. i accidently clicked this page

 

[OneLonelyBurrito]

I wonder why the switch, were the aluminum pistons having durability issues?
Did they keep the belt driven oil pump?

I think they switch to steel pistons to enable the increased torque output of the LZ0 vs the LM2. Yes, all 3.0L duramax's have belt driven oil pumps

 

[OneLonelyBurrito]

The UOA seems to show pretty low wear for this engine. For some reason, this engine likes to produce a lot of wear metals in UOA. Overall seems like a good report and a healthy engine.

 

[fantastic]

The 3.0L diesel is only used in full size trucks and SUV produced in North America. Along with the North American market, it is also exported to South America and Australia.

The engine launched in 2019 and 0W20 DexosD has been the recommend spec and viscosity for all sales regions (per the localized owners manuals) since the launch.

At launch, the engine was RPO LM2. In 2023, it transitioned to RPO LZ0. One of the big changes between LM2 and LZ0 is that LZ0 has steel pistons, where LM2 has aluminum.

My first thought about extra wear Fe would be the steel pistons, but with the OP's truck being a 2022, it is an LM2 with aluminum pistons.

Very good information. Thanks!

I wonder why the switch, were the aluminum pistons having durability issues?
Did they keep the belt driven oil pump?

Here's some data I found doing a quick bing search.
https://www.motorbiscuit.com/where-did-chevy-find-more-power-for-the-duramax-diesel-engine/


From Duramaxforum:
John Barta (John Barta, Chevrolet assistant engineer for diesel engines) was quoted as saying that in an interview printed on pickuptruck.com.

From: Exclusive: New 3.0L LZ0 Duramax Diesel fixes long-crank issue, extends belt life (pickuptrucktalk.com)

What’s new for the LZ0 Duramax Diesel?
Barta says about 25% of the parts on the LZ0 are different. The biggest change: steel pistons. These new steel pistons are narrower than the previous aluminum ones, which allows the piston stroke to be longer. That combined with new injectors allowed the engineers to retune the turbocharger to deliver more power. Torque is up 7.6% and horsepower is up 10%.
The big benefit of the LM2 was you could hit the maximum torque of 460 pound-feet at 1,500 RPMs. Hitting the torque at such a low RPM is what gives you the “throw you back in the seat” feel. Though Barta says the new LZ0 has a longer torque curve, reaching 490 pound-feet at 2,750 RPMs, you still get the 460 pound-feet at 1,500 RPMs. Basically, you still get the whiplash effect but also more power when passing and towing.