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Hello, I have a 2021 GMC Sierra SLT 6.2l. Its ben a great truck up until recently. At 42k miles, it started using 2+ qts of oil between changes. When I brought it in to the dealer they said the engines were being built "Too Loose" and suggested changing the pistons and rings. I let them do the work because I was approaching the 60k driveline warranty. When I picked the truck up, it seemed fine. I drove it for about 3 weeks and suddenly it started making noises like a rod knocking and engine backfiring. I brought it in and they now think its a rocker or who knows what else. I absolute love this engine but are pretty sure I'll trade it once O get it back. Anyone else experience this problem and is there any information on what years are better/worse on the 6.2l. At this point I'm not sure what to trade it for. Baby Duramax?

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Posted

IMO

What ever you decide to do is a roll of the dice. Good Luck.

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Posted
2 hours ago, Roy Juneau said:

Hello, I have a 2021 GMC Sierra SLT 6.2l. Its ben a great truck up until recently. At 42k miles, it started using 2+ qts of oil between changes. When I brought it in to the dealer they said the engines were being built "Too Loose" and suggested changing the pistons and rings. I let them do the work because I was approaching the 60k driveline warranty. When I picked the truck up, it seemed fine. I drove it for about 3 weeks and suddenly it started making noises like a rod knocking and engine backfiring. I brought it in and they now think its a rocker or who knows what else. I absolute love this engine but are pretty sure I'll trade it once O get it back. Anyone else experience this problem and is there any information on what years are better/worse on the 6.2l. At this point I'm not sure what to trade it for. Baby Duramax?

This is certainly not what we like to hear, Roy Juneau.  Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with the engine of your 2021 GMC Sierra. To do so, please send an email to [email protected] with ATTN: Roy Juneau/GM Trucks in the subject line.

Please include your contact information, VIN, a brief description of your concern, and the name of your preferred dealership. We look forward to hearing from you. To learn more about GM’s Privacy Policy, please visit https://www.gm.com/privacy-statement.html. The information you provide may be monitored and recorded and is subject to the GM Privacy Statement.
 
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  • 4 weeks later...
Posted

I have had a 2015 with about 55000 miles and 2019 that I traded in with around 19000 and now just over 20000 on my 2021 all with the 6.2 with no issues. Unfortunately it looks like you just got a "bad" one. 

 

  • Like 1
  • 1 month later...
Posted
On 6/29/2023 at 4:52 AM, Roy Juneau said:

Hello, I have a 2021 GMC Sierra SLT 6.2l. Its ben a great truck up until recently. At 42k miles, it started using 2+ qts of oil between changes. When I brought it in to the dealer they said the engines were being built "Too Loose" and suggested changing the pistons and rings. I let them do the work because I was approaching the 60k driveline warranty. When I picked the truck up, it seemed fine. I drove it for about 3 weeks and suddenly it started making noises like a rod knocking and engine backfiring. I brought it in and they now think its a rocker or who knows what else. I absolute love this engine but are pretty sure I'll trade it once O get it back. Anyone else experience this problem and is there any information on what years are better/worse on the 6.2l. At this point I'm not sure what to trade it for. Baby Duramax?

Hey Roy, any resolution from GM on your engine?

  • 1 year later...
Posted
1 hour ago, Jjc1229 said:

This same thing is happening to my 2021 Yukon. Burning 2+ liters in between oil changes.  

Welcome to the forum. How many miles on your truck?

  • 2 weeks later...
  • 3 weeks later...
Posted

With 125,000 on our '15 6.2 it uses less than a quart between changes and I go by the DIC for oil changes - changing around 10% life left. 

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