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Cylinder Head - Valve - Lifter / Lash Adjuster Replacement on new 2021 Tahoe Z71

Rich Hanley
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newdude Senior Enthusiast

newdude

Posted
Posted (edited)

No, you didn't get a lemon. 

 

Yes, there has been a rash of AFM/DFM lifter failures in the past year.  Dealer will fix it and it will be all good again.  Typically its a lifter or lifters, plus any bent pushrods.  If you have a cylinder fail on each bank, dealer will replace all 16 lifters.  If one bank had the failure, that entire one bank will get 8 lifters.

Edited by newdude
Acey76 New Member

Acey76

Posted
Posted

Happened to me around 5,000 miles.  2021 Suburban z71 5.3.  

 

First time left bank, 3 weeks later right bank..  

 

Almomst 3 weeks in the shop.

 

Seems to be good now!

newdude Senior Enthusiast

newdude

Posted
Posted
17 hours ago, Rich Hanley said:

Pretty severe bend in the push rod. Is there a way to disable the DFM system and/or is GM issuing a recall?

 

 

 

No recall.  Not sure what GM has layed out for any plans other than fixing the ones that break.  

 

None of the AFM/DFM disable devices work on Tahoe/Suburban/Yukon/Escalade.  These SUV's are on GMs all new Vehicle Intelligence Platform or VIP which replaces Global A architecture for vehicle electronics and module communications.  The ECMs have not been "cracked" if you will, nor has anyone validated fitment of devices like the Pulsar LT to work.  

  • 2 weeks later...
Cantrell Enthusiast

Cantrell

Posted
Posted

There is another thread on this.  It speaks to the errors that are shown when this happens.  My truck has been at the dealership for over a month now.  Still waiting on parts.  There is nothing I or they can do but wait on GM to deliver.  The sad thing is that they knew exactly what was wrong when I dropped it off.  

MAC21 Enthusiast

MAC21

Posted
Posted

Been in for 21 days now.  Just hear from dealer. Parts will be in tomorrow.  Replacing all 16 and guides.  Looking forward to having my brand new truck back!  

Cantrell Enthusiast

Cantrell

Posted
Posted

I just got the call from the dealership.  My truck is ready.  I stopped by there the other day and spoke to the technician.  He had them order parts for all cylinders so the top of the engine was completely tore down while I was there.

GM suggested that I test drive the truck with the technician so I could point out anything that I thought was not normal.

I also spoke to GM about lemon law and options.  They said they were working on rebuilding trust in GM vehicles and were willing to discuss reimbursement option if I decided not to follow the lemon law route.

 

If all is well and accepted, it will have been at the dealership for 38 days.

Rich Hanley New Member

Rich Hanley

Posted
  • Author
Posted

Make sure they put a new serpentine belt on after the repair. The dealership did not do that for my vehicle and that left us stranded on the highway for 5 hours in 100 degree weather waiting for a tow truck. Not to mention the $800 for towing, lodging and repair at another Chevrolet dealership. Could have easily been avoided…

Cantrell Enthusiast

Cantrell

Posted
Posted

They did not put a new belt on.  What would warrant a new belt?  I am not at all saying you are wrong.  Just curious why?

 

Cantrell Enthusiast

Cantrell

Posted
Posted

GM is offering me compensation.

Just not sure if I should try to lemon law my truck, even though I guess it is fixed now.

Or, maybe try to exercise a buy back or something like that.  Only problem is, trucks a pretty slim pickens right now.

Rich Hanley New Member

Rich Hanley

Posted
  • Author
Posted
1 hour ago, Cantrell said:

GM is offering me compensation.

Just not sure if I should try to lemon law my truck, even though I guess it is fixed now.

Or, maybe try to exercise a buy back or something like that.  Only problem is, trucks a pretty slim pickens right now.

What is GM offering you?

 

1 hour ago, Cantrell said:

They did not put a new belt on.  What would warrant a new belt?  I am not at all saying you are wrong.  Just curious why?

 

If they 

  • 1 month later...
5rings New Member

5rings

Posted
Posted

just wondering if folks have heard of offers from gm "to rebuild trust".  my z71 is in the shop for 14 days now. broke down with lifter problem and cyljnder misfire at 10000 miles and while we were on a 2 week road trip. 

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