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Posted (edited)

Picked up my 21 LT TB 6.2 on Wednesday night, put maybe 170 miles on it and upon start up this AM was greeted with slightly rough running which transitioned to PO106, PO300 and PO506 and the truck refusing to run. 

Based on the symptoms and the sound while attempting to crank, like it was down compression in at least one hole - I’m betting on a valve spring. 
 

Obviously, a down new truck is a bummer. I’ll be putting around the forums here looking for some other sob stories to make me feel better. If the experienced guys here have any input or think my issues may be less severe - we’ve got until Monday at the earliest to argue about it when the dealer should dig into it. 
 

Since pics get peoples motors running, here’s the one I have after getting the topper installed the day after I picked it up - Thursday 🙁

 

 

 

image.jpeg

Edited by zbomb
Can’t type
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Posted

Wow That sux, Hope they get it sorted out and get you back on the road ASAP.

 

Posted
2 hours ago, WeGone said:

Wow That sux, Hope they get it sorted out and get you back on the road ASAP.

 

 

Me too brother - I'm pretty jacked up about the whole thing. 

Posted

so much for the issue being resolved i guess, unless you got one thats been sitting on a lot for a while

Posted
2 hours ago, putz173 said:

so much for the issue being resolved i guess, unless you got one thats been sitting on a lot for a while

 

I took delivery the day it hit the dealer lot, had a deposit on it for a month or so waiting for the dealer to receive it.

 

I am looking forward to hearing what the dealer who is doing the diagnostics reports back tomorrow.

 

I'll keep hoping for something minor, but I am really not expecting good news. Plan for the worst hope for the best, right...

Posted

Believe the hope was anything built after March '21 shouldnt have lifter issues, but engines do sit around between being built and put into vehicles

 

be interesting to know your build date if it ends up being lifter issue

 

wonder if the EPA knows forcing this garbage on GM with DFM and auto start stop probably results in more emissions than its saving over the lifetime of the vehicle then the extra trips to dealerships use

Posted

Got a service advisor (not mine, she’s MIA) to give me an update - Tech’s requesting Valve Spring(s)… he could not confirm one or all - it better be all. 
 

Will provide additional info as I get for any other unfortunate souls in this position. 
 

BTW - my build date is 7/15/21 which falls well outside the scope of GM issued technical bulletins on this issue with the most recent doc I have seen, dated 6/1/21 saying affected dates being between 7/1/20 and 12/16/20…

Posted

SA confirmed broken valve spring CYL 4 and they are planning to only replace the broken spring. 
 

Not happy and will be working to get some satisfaction here. 

Posted
10 minutes ago, zbomb said:

SA confirmed broken valve spring CYL 4 and they are planning to only replace the broken spring. 
 

Not happy and will be working to get some satisfaction here. 

Talk to your girlfriend about that!  Ha.

 

What are you expecting GM to do besides fix it under warranty?

Posted

Well - since this issue is widely known, and the guidance under PIP5752M was to replace all springs - I expect them to replace all springs. That was the guidance when GM still acknowledged this to be an issue - I don’t think that just because GM has decided to not acknowledge the issue still exists, my truck should be treated differently for the repair process. Failure mode same, repair the same way. 
 

What would you accept on a truck with 200 miles ?

  • Like 1
Posted

I sure would want the compression checked in each cylinder. and then when i got it home i would infrared check each exhaust... 

Posted
38 minutes ago, TxTruckMan said:

Talk to your girlfriend about that!  Ha.

 

What are you expecting GM to do besides fix it under warranty?

I have seen it here a few times were cheap GM instead of doing what's right and replacing them all, decided to only do one side and within a few weeks guess what happens, yes the other side goes bad!

 

Some people kind of spend the 50+ grand on a new truck so they can trust what they are driving, hard to do that whe known problems are allowed to continue because Gm doesn't have the parts to fix their problems correctly. Let's face it that is the true reason why they seem to be going away from the correct procedure with replacing them all, trying to hope that the remaining parts hold up. Not cool if you ask me when you have made like 1 or 2 payments on the thing!

Posted
50 minutes ago, zbomb said:

Well - since this issue is widely known, and the guidance under PIP5752M was to replace all springs - I expect them to replace all springs. That was the guidance when GM still acknowledged this to be an issue - I don’t think that just because GM has decided to not acknowledge the issue still exists, my truck should be treated differently for the repair process. Failure mode same, repair the same way. 
 

What would you accept on a truck with 200 miles ?

Ok, sure.  I'd mention that to your service manager.  If the guidance says to replace them all, then that seems fair.

 

I thought you might have been asking for something crazy like GM to pay your car note or a full buy back or something.  Some people seem to think they're owed unreasonable things for being slightly inconvenienced.

 

A thorough troubleshooting and repair is not an unreasonable ask.

Posted

What I want:

 

1. Follow the same repair procedure that would have been carried out for the acknowledged build dates with the issue - it is clear that although my build dates fall outside the acknowledged dates, the issue persists - Replace all valve springs as detailed in PIP5752M (and maybe investigate the scope of the issue and if the bulletin dates need to be reassessed)


2. Perform leakdown, compression and inspection of the oil filter to assure no peripheral damage occurred from the valve spring failure. 
 

That’s it… 

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