Code P06DD thrust bearing issue...

[Stbentoak]

It now appears there is a thrust bearing issue erupting on January 1st through September 1st, 2025-26 LZ0's. Nobody really knows what the extent is or if it affects every vehicle or not. But potentially it is grenading engines, just like the 6.2 issue. If anybody has any knowledge about this that's legit. Would be good to hear about it here......

Don't turn this into an oil issue. This is a faulty part issue. And the issue is whether it's all of them produced... some of them produced...... Or a hit or miss ticking time bomb like the L87 issue....

 

[blanchard7684]

 

[pa31p]

This one perhaps

GM TSB 25-NA-307

 

[Skiwagon25]

Just past 6600 miles on '25 AT4, June '25 build date. Attached oil analysis from my 4880 mile oil change that had 3,868 miles on the oil, with one towing trip. Had my first oil change at roughly 1200 miles.

Silicon is high, which for the break-in period is not a concern yet.

However, the total metals and wear/1000 miles has me concerned, I have used XPD in my fuel.

 

[Fless]

Just past 6600 miles on '25 AT4, June '25 build date. Attached oil analysis from my 4880 mile oil change that had 3,868 miles on the oil, with one towing trip. Had my first oil change at roughly 1200 miles.

Silicon is high, which for the break-in period is not a concern yet.

However, the total metals and wear/1000 miles has me concerned, I have used XPD in my fuel.

Are you saying that your UOA has something to do with the thrust bearing issue?

 

[Skiwagon25]

Just providing data, for what's its worth. Is the wear related? I have no idea, could be break in too, but this is oil change #2 and would have hoped the wear would not be a flagged item.

 

[Stbentoak]

I wouldn't be too impressed with any analysis that recommends going outside the Dexos D standards. Neither of their recommended oils are even close to the right composition for this engine. And just for the record, there is a Amsoil Dexos D that IS 5W 30. They didn't recommend that.....

 

[StephenPT]

LZ0 3.0 Duramax: GM Flags Crankshaft End Play Behind Bellhousing Noise & P06DD (25-NA-307)

GM bulletin 25-NA-307 (LZ0 3.0 Duramax, 2025–2026) links bellhousing-area noise + MIL/P06DD to excessive crankshaft end play (possible thrust-bearing failure). Dealers should measure end play at the crank pulley bolt with a dial indicator; spec is 0.084–0.316 mm (0.0033–0.0124 in). Expect to pay...

www.duramaxnews.com

 

[StephenPT]

Just past 6600 miles on '25 AT4, June '25 build date. Attached oil analysis from my 4880 mile oil change that had 3,868 miles on the oil, with one towing trip. Had my first oil change at roughly 1200 miles.

Silicon is high, which for the break-in period is not a concern yet.

However, the total metals and wear/1000 miles has me concerned, I have used XPD in my fuel.

Here's the two UOA I've done - first sample is on the right, most recent sample on the left. I have a '22 LM2.

 

[DuraYuk]

My wife's 2025 yukon xl has a bit over 8k miles. Im not worried. It has a 5 year 100k miles powertrain warranty. If by bad publicity they extend that im good with it!

No issues to report....yet. time will tell.

Id imagine they dont want the bad publicity the 6.2 got them so they trying to get ahead of it.

On Facebook it looks like most with issues have really low mileage.

Ours was built week of 4/14/25

 

[Stbentoak]

My wife's 2025 yukon xl has a bit over 8k miles. Im not worried. It has a 5 year 100k miles powertrain warranty. If by bad publicity they extend that im good with it!

No issues to report....yet. time will tell.

Id imagine they dont want the bad publicity the 6.2 got them so they trying to get ahead of it.

On Facebook it looks like most with issues have really low mileage.

Ours was built week of 4/14/25

That's what I'm seeing too. It looks like if you potentially clear say the 5000-mile mark. You possibly could be in the clear. Don't have many facts to back this up, but it does appear that most failures are quite quickly after delivery.

 

[TiGrayMSM]

I wouldn't be too impressed with any analysis that recommends going outside the Dexos D standards. Neither of their recommended oils are even close to the right composition for this engine. And just for the record, there is a Amsoil Dexos D that IS 5W 30. They didn't recommend that.....

Speediagnostix is a very reputable source. Their videos on oils/filters (The Motor Oil Geek) are very informative. The Mobil 1 0w30 ESP, from my understanding, is the same base formulation of that of the Dexos D certified 0W20 ESP. The 5W30 Dexos D oils are for the for 2.8L. UoAs for the 3.0 Dmax using 0w30 show less wear metals and is likely why that recommendation is included.

 

[Stbentoak]

Speediagnostix is a very reputable source. Their videos on oils/filters (The Motor Oil Geek) are very informative. The Mobil 1 0w30 ESP, from my understanding, is the same base formulation of that of the Dexos D certified 0W20 ESP. The 5W30 Dexos D oils are for the for 2.8L. UoAs for the 3.0 Dmax using 0w30 show less wear metals and is likely why that recommendation is included.

If you have this failure and you don't have DexosD in there. (and they will check...) It is real grounds for denying your warranty. But you do you.....

 

[TiGrayMSM]

If you have this failure and you don't have DexosD in there. (and they will check...) It is real grounds for denying your warranty. But you do you.....

Exactly why I am personally still running 0W20 Dexos D during the warranty period. I recently switched to Castrol Turbo Diesel Dexos D 0W20 (from AcDelco) and hope to see a decrease in wear metals, especially iron.

 

[Flathead40]

We have nearly 10k on our AT4 XL and have not noticed anything out the usual, so cautiously optimistic we are ok. I don’t think they know enough yet to say if this could affect all 25-26 LZ0s or if it’s limited to a certain set of build dates. I would guess that they would issue a recall if it’s clear that this is a catastrophic defect that result in loss of motive power. But if they can narrow it down to a specific set of VINs that are affected the better for GM.

 

[Siginsde]

Unfortunately my 2025 Denali, 3251 miles, was towed in this week with the P06DD. I puchased September 3rd. I am being told I need a new oil pump and turbo and advisor wasn't very enthusiastic about parts coming in a timely matter. Hopefully parts come in and the advisor is just buying time. Specifically bought the Diesel to avoid the 6.2 problems.

 

[Scarey]

Start exploring your states lemon law. Forewarned is forearmed.

 

[Polo08816]

It now appears there is a thrust bearing issue erupting on January 1st through September 1st, 2025-26 LZ0's. Nobody really knows what the extent is or if it affects every vehicle or not. But potentially it is grenading engines, just like the 6.2 issue. If anybody has any knowledge about this that's legit. Would be good to hear about it here......

Don't turn this into an oil issue. This is a faulty part issue. And the issue is whether it's all of them produced... some of them produced...... Or a hit or miss ticking time bomb like the L87 issue....

This one perhaps

GM TSB 25-NA-307

... and people here said that the baby Duramaxes were the more reliable GM engines...

... what is wrong with GM these days?

 

[Jayhawkeye3]

Well this sucks after buying a 100k vehicle and putting another 12k in it. I too bought diesel to avoid the 6.2 issues.

No issues so far after 1400 miles. Are people taking them in proactively to check?

 

[Stbentoak]

... and people here said that the baby Duramaxes were the more reliable GM engines...

... what is wrong with GM these days?

Well based on mine and other LM2's... It has been rock solid for 40K+ miles. LZ0 was supposed to be an improvement over LM2 but not with components that are not up to par for the job.

Unfortunately my 2025 Denali, 3251 miles, was towed in this week with the P06DD. I puchased September 3rd. I am being told I need a new oil pump and turbo and advisor wasn't very enthusiastic about parts coming in a timely matter. Hopefully parts come in and the advisor is just buying time. Specifically bought the Diesel to avoid the 6.2 problems.

I am at the same mileage you are on my 25. So far so good.... But I'm nervous. I don't have a lot of faith in a dealer fix for this issue or having an engine replacement. Both of them are heavy issues that usually don't turn out well. Fingers crossed that mine is one of the good ones. I count on this vehicle every day and don't have a backup plan......