Bradley E

I have had this same issue. Filter and flush, then torque converter. None of that helped. It’s now at the dealer after a lifter failureX2 (it ate itself after the test drive for the first repair) Now they are replacing the whole motor because GM engineering said so. must of did some good damage. Oh, it’s a 2019 AT4 with 35k miles….

Just found this after replying to another thread. Just reading up. Waiting on a motor swap on my 19 AT4. Bank 2 failed and ended up taking out others on the test drive after the repair. Engineer said to replace the motor. They mentioned to the tech advisor that these engines have poor oiling which doesn’t help the lifter failure problem. I’ve had shuddering and bucking for a while. they thought it was a trans problem and began this journey with fluid flush and filter. Didn’t help. So in went a new torque converter. I ran it a while until the problems surfaced quickly and I called for another appointment. 5 minutes later…. boom! clack clack clack. lol

My 19 AT4 just had lifter failure at 35k miles. I know this is an old thread, but just goes to show, at 4 years old, it’s only a matter of luck i guess! Fixed Bank 2 only to have others come apart on the test drive after. Gm engineer told the tech to replace the whole motor. They also mentioned inadequate oiling in these motors. No wonder you don’t see any on the lots currently…