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2021 Sierra at4 Engine Knocking

JonTheDon
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JonTheDon New Member

JonTheDon

Posted
Posted

I    So I picked this truck up in December of ‘20 and I’ve been in love with it ever since. This is a 6.2 btw with about 13k miles. A few days ago on the way into work, I noticed a weird shake that felt like a rough gear shift, which isn’t TOO out of the ordinary. After exiting the freeway, I have it some gas to get over lanes and I felt the ugliest shake ever from the truck. Noticed it only happened with light pressure on the gas so got to work and left it alone. went home and drove fine that day. 
   Next day comes and take a drive about 20 miles and nothing too strange until on my way back home I start hearing a quick paced ticking from the engine bay. And then with light pressure on the gas, it starts to knock. Finally got a check engine light and this thing is knocking and ticking like crazy. Going to have it taken to the dealer tomorrow. Not sure what to expect. Also, got an on star alert that “ an issue with engine and transmission system has been detected”. 
   Anyone experience this yet? Or any similar issues? 
 

Here’s a vid of how it sounds 

 

Greystone21 New Member

Greystone21

Posted
Posted

See my post today. I too had same issue with 2021 Sierra 1500 5.3L V8. Had vehicle towed to dealership yesterday. Determined it is a damaged lifter. Wont know extent of engine damage until they dig in later this week. Mentioned this is the 4th one this year and two were complete engine replacements. Very disappointed. Looking at options if they come back with repair and not replace engine. I only have 5.370 miles on this 2021 and purchased it in October 2020.

 

This may be a bigger issue than GM is willing to recognize. 

Dprince New Member

Dprince

Posted
Posted

Just had my 2021 with 7100 miles towed in yesterday and was told it was a failed lifter. Don’t know the extent of the damage till it’s torn apart. What is going on??? I am extremely disappointed. 

  • 2 weeks later...
Michael Choquette New Member

Michael Choquette

Posted
Posted

Sadly, I too have experienced the lifter failure. I'm at 11,7xx miles. 2020 Sierra with 6.2l. Waiting to see what dealer says if they can see bend rods, or damage to pistons. 

  • 6 months later...
Rene Kars New Member

Rene Kars

Posted
Posted

Yep, same here started with an intermittent knock yesterday, wanted to leave for family visit this morning and have awful knock which let me believe lifter failure, 2021 Sierra 1500 5.3L V8 with 8100 miles. Will have to tow to dealership tomorrow, absolutely sucks

M1ck3y Senior Enthusiast

M1ck3y

Posted
Posted

That's hilarious, Onstar notifies you that you have an engine problem. Just incase you didn't notice :lol:

 

I'd put money on a blown lifter.. Wasn't there a issue of failing rocker's/spring's with lt1/lt2/l87, or something along those lines?

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