My 2018 Tahoe with 5.3L had catastrophic engine failure at 67k miles just outside the powertrain warranty. Low oil pressure indicator light, occurred on a road trip. Followed service schedule to manufacture recommendations. Pulled vehicle over right away when it occurred, let it rest for 45 min hoping it was a sensor, dipstick showed not low on oil. Restarted with heavy knock. Had it towed to nearest Chevy dealer and service department identified issue as broken rod bearing and that engine needed to be replaced.
This occurred in July 2022 and Tahoe has been in shop ever since waiting for a replacement engine. In November I received an update that there were 2000 on backorder and I was about #1000 on list, GM was slotted to get first round of inventory in December if first 100. Was told i should expect mine sometime in Q4 of 2023.
No loaner and still making payments on GM Financial loan and auto insurance on a car that is dead. The only light at the end of this story is I was able to persuade GM to cover it under the powertrain warranty. Originally dealer tried to bill me $14k for parts and labor.