I have a 2021 Sierra 1500 AT4 with the 3.0, it was in the shop for 2 months. They replaced the exhaust system twice and the Nox sensors once. They released it after thier third attempt saying it was fixed. Unfortunately, the light came back on after 48 miles. The code is the same P2382. Sense it is still under warranty and GMC is screwing me around. I retained a lemon law firm probono. GMC is obligated to buy your truck back and compensate you for any collateral damages.