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Posted

Oh man. Don’t I hate knowing I bought something this expensive with an issue like this. Thanks for the info though.

  • Like 1
Posted

Cut and past from the GM notice posted elsewhere:

 

Some 2020 Silverado, Sierra; 2020-2021 Camaro; 2021 Corvette, Tahoe, Suburban, Yukon, and Escalade models equipped with the 5.3L engine (RPOs L82, L84), 6.2L engine (RPOs L87, LT1, LT4, LT2), or 6.6L engine (RPO L8T) may have a misfire and engine noise condition. The Check Engine MIL also may be illuminated along with several possible DTCs, including DTCs P0300, P0106, P0506, P3189, P318A, P318B, P318C, P318D, P318E, P318F, and P3190. These conditions may be due to a broken valve spring.

If it’s determined during an inspection that the engine has a broken valve spring, a cylinder leakage test on the affected cylinder must be performed.

 

5.3L and 6.6L Engines

On 5.3L and 6.6L engines (RPOs L82, L84 and L8T) built from June 1, 2020 to October 7, 2020, if cylinder leakage is not observed, replace only the affected valve spring. (Fig. 13)

 

6.2L Engines

On 6.2L engines (RPOs L87, LT1, LT4 and LT2) built from June 1, 2020 to October 7, 2020, if cylinder leakage is not observed, replace all valve springs on both cylinder banks.

  • Like 1
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  • 2 months later...
Posted
16 hours ago, awesome barney said:

Anyone with that build date with a 6.2 make it past 5000 miles?

Just at 7,000.   And it's been broken in rough.  A few trips down the 1/4 mile and some other "spirited" driving.  

  • 2 weeks later...
Posted

4000 miles here, 8/20 build, no issues with the engine yet, leaky rear window is an entire other story...

 

as a side note....It does seem like the lifters in these new dynamic fuel management V-8s are failing early in life cycles..

Posted

4000 miles here, 8/20 build, no issues with the engine yet, leaky rear window is an entire other story...

 

as a side note....It does seem like the lifters in these new dynamic fuel management V-8s are failing early in life cycles..

Posted
49 minutes ago, RadBrad said:

4000 miles here, 8/20 build, no issues with the engine yet, leaky rear window is an entire other story...

 

as a side note....It does seem like the lifters in these new dynamic fuel management V-8s are failing early in life cycles..

New dmf victim checking in 8500 mile failure

Guy walked in service department at the same time with 21 at4 suv whose pushrod was bent to all hell, dealer in Florida changed it and lifter job but app sent him alerts a week later so he pulled up to our dealer to show documents and codes,

 

 

didn’t sign up for this kinda failure, in 3rd year of a platform 

 

Posted
4 minutes ago, CLandry said:

New dmf victim checking in 8500 mile failure

Guy walked in service department at the same time with 21 at4 suv whose pushrod was bent to all hell, dealer in Florida changed it and lifter job but app sent him alerts a week later so he pulled up to our dealer to show documents and codes,

 

 

didn’t sign up for this kinda failure, in 3rd year of a platform 

 

Oh man, that's not good, I've heard of a couple guys here where I live too that have had issues with the lifters.  I was really hoping the older AFM lifter issues might have been resolved with this new DFM, but obviously not.  Its crazy this fuel management stuff has been around since like 2010 or something like that....you would think in a decade things can be improved to work without failure, especially early failure.  Your right, it really isn't acceptable.    

  • 4 weeks later...
Posted (edited)
On 12/19/2020 at 11:46 PM, Rob Mugs said:

I just had the exact same thing happen yesterday on my 2021 Sierra Denali with only 3800 miles on it... So pissed!!
 

 

Agreed.. it's not his problem.  He didn't design, engineer, or build the truck.  He just sold something he thought would be working.

 

@SILVER SLED, she barely can maintain idle.  CEL is on but OnStar says no issues.  I wasn't on it either;  I was at 50 mph and cruising when I felt what seemed like a flat tire at first.  Over a period of ~15 to 30 seconds it went from that to sounding like a lifter tick to a full-on bang sound.

 

Been a GM guy for 20+ years..... had two Fords with no issues.  This isn't leaving a good taste in my mouth

 

Edited by Snow135
  • 2 weeks later...
Posted
On 12/19/2020 at 10:40 PM, JimCost2014 said:

And at this point, the truck is owned by the bank (or the OP) , not the dealership, salesperson, or GM.

The dealer can call the bank and "swap collateral " if thats the route they go. I'd rather get a new engine that has been updated rather than another truck on the lot that may do the same thing. 

 

GM needs to get this under wraps pretty quickly...

Posted (edited)
On 12/19/2020 at 10:40 PM, JimCost2014 said:

And at this point, the truck is owned by the bank (or the OP) , not the dealership, salesperson, or GM.

The dealer can call the bank and "swap collateral " if thats the route they go. I'd rather get a new engine that has been updated rather than another truck on the lot that may do the same thing. 

 

GM needs to get this under wraps pretty quickly... Here's a brand new 21 Yukon with an engine knock fresh off the hauler 3 weeks ago.

 

 

Resized_20210505_090523.jpeg

Edited by 20Denali21
Posted
On 4/23/2021 at 1:04 AM, CLandry said:

New dmf victim checking in 8500 mile failure

Guy walked in service department at the same time with 21 at4 suv whose pushrod was bent to all hell, dealer in Florida changed it and lifter job but app sent him alerts a week later so he pulled up to our dealer to show documents and codes,

 

 

didn’t sign up for this kinda failure, in 3rd year of a platform 

 

 

Actually it is far worse than that as this has been an ongoing issue since they released the newer DI engines back at the start of the 14 model year, yes this has been an issue for 8 years now. Seems it has just been allowed to continue, you would think a part supplier or design change would of been implemented in the last 8 years but here we are!

Posted
On 5/26/2021 at 10:55 AM, BIGDOGx said:

 

Actually it is far worse than that as this has been an ongoing issue since they released the newer DI engines back at the start of the 14 model year, yes this has been an issue for 8 years now. Seems it has just been allowed to continue, you would think a part supplier or design change would of been implemented in the last 8 years but here we are!

Just to be clear, my case was NOT a pushrod issue.  It was a broken valve spring that grenaded the motor

Posted
On 5/27/2021 at 10:48 PM, Rob Mugs said:

Just to be clear, my case was NOT a pushrod issue.  It was a broken valve spring that grenaded the motor

Yes and like i said it has been an ongoing problem for 8 years now. Collapsed Lifters which lead to bent pushrods and valve springs breaking are all 6.2 issues that have been happening since the 14 model change.

Posted (edited)
26 minutes ago, BIGDOGx said:

Yes and like i said it has been an ongoing problem for 8 years now. Collapsed Lifters which lead to bent pushrods and valve springs breaking are all 6.2 issues that have been happening since the 14 model change.

The valve spring issue in the 6.2's is a completely separate issue from the lifter issue and is a much more recent event. 

 

A collapsed lifter, happening for a while now on GM's engines, will short stroke a rocker arm creating less stress on a valve spring, not more.

Edited by Gangly

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