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Posted
14 hours ago, Nutmeg said:

Since I have a factory disabled 5.3 that makes me feel better. Previous was a 08 5.3 AFM that I traded at 100k that never had an issue.

Question on the bad batch of lifters. Are the Sept 2020 to March 2021 engine dates or vehicle completion dates?

 

 

Lifter production dates.  GM had to special return lifters in stock in the date code range, they had a special return on crate engines and VLOM kits as well.  

Posted (edited)
On 1/19/2022 at 7:53 AM, newdude said:

 

 

Lifter production dates.  GM had to special return lifters in stock in the date code range, they had a special return on crate engines and VLOM kits as well.  

So if you had a build date of 3/21/21 you would be in the (bad lifter range)I would guess the motor was built at least a few weeks+  before build date?

 

Update:  So my engine build date is Feb 25 21

 

IMG_5336.jpeg

Edited by WeGone
Posted (edited)
8 minutes ago, WeGone said:

So if you had a build date of 3/21/21 you would be in the (bad lifter range)I would guess the motor was built at least a few weeks+  before build date?

 

 

Julian date range was 20245 to 21063.  So September 1st 2020 to March 4th 2021.  This is the exact target range of possible defective lifters produced in the parts network, part kits, engines.

Edited by newdude
Posted (edited)

Someone posted on one of these threads that they had a build date of 8/21, which is supposed to be after the range date, and also a no dfm, and he has the problem. sounds lile it anyway, it started shaking bad, died, then wouldnt start.

Edited by AD80
Posted

I have seen on a facebook group a GM Tech showing 2022 models with under 5k miles showing up with lifter failures.

Posted

Too bad there was never a resolution posted in the below thread. His truck had no DFM.

 

 

Posted
22 hours ago, Jricharc said:

I have seen on a facebook group a GM Tech showing 2022 models with under 5k miles showing up with lifter failures.

Dude stays busy. I wonder if some of these 22 Limited trucks were 21's that sat too long after assembly and then switched to 22's. 

Posted
On 1/19/2022 at 2:18 PM, Byrds8 said:

Too bad there was never a resolution posted in the below thread. His truck had no DFM.

 

 

 

Pretty hard to attribute that issue to a failed DFM lifter.  Given it wouldn't start after all the racket he described, I would suspect it was something a little more dramatic.

Posted

I bought my TB without AFM from the factory and am just north of 2000 miles with a build date in July of 2021. Very curious about this topic as well. I know that it has been said that these engines still come with the collapsible lifters on 4 cylinders but I would still like confirmation from an actual engine tear down. I just hope it won’t be mine…

Posted
9 minutes ago, Desrunner said:

I bought my TB without AFM from the factory and am just north of 2000 miles with a build date in July of 2021. Very curious about this topic as well. I know that it has been said that these engines still come with the collapsible lifters on 4 cylinders but I would still like confirmation from an actual engine tear down. I just hope it won’t be mine…

 I maybe wrong but as DFM works randomly on all 8 cylinders , I would not think GM would only put in 4 even without the chip to activate it.

Posted
14 minutes ago, WeGone said:

 I maybe wrong but as DFM works randomly on all 8 cylinders , I would not think GM would only put in 4 even without the chip to activate it.

He has a Custom Trail Boss with the L82 AFM 5.3 as opposed to the L84 DFM 5.3. The L82 has the older AFM system that is only present on four of the cylinders. With half of the movable lifters, mathematically it's half as likely to fail, but I believe the parts on those four cylinders are similar/the same (albeit with a different control/oiling system).

Posted

2019 RST4x4 5.3. 24,000 to date no issues. I am in the minority in that I don't mind the DFM my lifetime mpg is over 20 mpg. The system seems pretty seamless the microsecond delay to full power is not an issue for me. 2019 being the first year with the new DFM  I purchased the extended warranty for 7 years if it breaks I'll get it fixed. In the meantime I will be out enjoying this technical marvel to its fullest! I say technical marvel because I grew up riding and driving in 70's and 80's trucks these new T-1's are complex machines that are powerful and capable get out and enjoy! 

Posted
1 hour ago, voided3 said:

He has a Custom Trail Boss with the L82 AFM 5.3 as opposed to the L84 DFM 5.3. The L82 has the older AFM system that is only present on four of the cylinders. With half of the movable lifters, mathematically it's half as likely to fail, but I believe the parts on those four cylinders are similar/the same (albeit with a different control/oiling system).

Thanks for the clarification did not know AFM was still used at all!!

 

Posted
3 hours ago, WeGone said:

Thanks for the clarification did not know AFM was still used at all!!

 

The 2021 model year was the last for the L82 AFM version of the 5.3, as well as the 4.3 V6 with AFM. The 2022 LTDs and 2022 refresh models won't have those, only the DFM L84 5.3. The currently-available 2.7 turbo I-4 has a different variant of AFM that shuts off two of the four cylinders, though.

Posted
6 hours ago, voided3 said:

He has a Custom Trail Boss with the L82 AFM 5.3 as opposed to the L84 DFM 5.3. The L82 has the older AFM system that is only present on four of the cylinders. With half of the movable lifters, mathematically it's half as likely to fail, but I believe the parts on those four cylinders are similar/the same (albeit with a different control/oiling system).

Correct, L82 with the 6 speed and -$50 (credit) for not having AFM. I drove the L84 with the 8 speed and was not a fan, which had AFM and start/stop. 

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