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Posted

Hi, I'm currently considering purchasing a GMC AT4X with the 6.2 engine, and I've heard about potential issues with DFM (Dynamic Fuel Management) lifter failure. Can you provide more information on the reliability of the DFM system in this specific model? Should I be concerned about potential lifter failures, and are there any preventative measures or updates that have been implemented to address this issue? Thank you

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Posted

Welcome to the forum.

 

Don't change the oil past 5k miles.  Probably one of the best preventative measures.  AFM and DFM gotta have good and clean oil.  Long drains can be too harsh on the properties of the oil that prevent it from shearing or aerating.  

 

No parts have changed, same lifters are still in use.  

 

Lately on 6.2s there are reports of main or rod bearing failures.  Our sister dealer replaced 3 engines in 6.2s that were 2022 model year.  

 

For future Sierra questions, head over to the Silverado/Sierra forum section rather than the Traverse/Acadia section.

 

Here's the 2019-current forum section - 2019-2025 Silverado & Sierra - GM-Trucks.com

 

 

  • 1 month later...
Posted
On 2/7/2024 at 10:27 PM, newdude said:

Welcome to the forum.

 

Don't change the oil past 5k miles.  Probably one of the best preventative measures.  AFM and DFM gotta have good and clean oil.  Long drains can be too harsh on the properties of the oil that prevent it from shearing or aerating.  

 

No parts have changed, same lifters are still in use.  

 

Lately on 6.2s there are reports of main or rod bearing failures.  Our sister dealer replaced 3 engines in 6.2s that were 2022 model year.  

 

For future Sierra questions, head over to the Silverado/Sierra forum section rather than the Traverse/Acadia section.

 

Here's the 2019-current forum section - 2019-2025 Silverado & Sierra - GM-Trucks.com

 

 

Did they fix the issues on the 2024 or 2025 6.2s? I am not hearing too much on the recent models. 

A new generation is just round the corner also....

 

  • 5 months later...
Posted
1 hour ago, Suregrip391 said:

Interested to know as well……considering a new truck. 

I am a 30 yr mechanic. Chevy dealer included. I just ordered a `25 Silverado with the 5.3. So, the lifters and bearings don`t seem to bother me.

 

All manufacturers are having problems these days. Pick your poison.

 

I will say, mine will get 5 or 10w30 with 3000 to 4000 OCI. Screw their 0w20 and long OCI`s.

  • Like 1
Posted

I've posted this same answer in another forum with the same question. It's really luck of the draw and maintenance. I've had a 10,14,16,20, and now a 24. No issues out of any of them! All of them either had DFM or AFM and were not disabled in any way.

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