Tim, I watched the YouTube for this one and you're cracking me up lol. You fight so hard to not blame the manufacturer.
The article states "Two relevant production periods at the Alabama plant were identified between the production period covered by recall 24V-381 and the implementation of a design change to increase the robustness of the #1 main bearing"
If the engineered main bearing type and size or strength were not correct for the job leading to failures, partially possibly due to debris in the engine,... isn't that by definition a design flaw?
They're not saying the bearing manufacturer made a mistake and the bearing wasn't made to spec. They're saying they had to go back to the drawing board and design a new main bearing.
I'm just a moron with a keyboard but I'm sticking to what I said a couple of years ago on this topic. It's possible and likely manufacturing debris was causing some of these issues. It's also likely the meain bearings, and oil delivery, were flawed in some way. Too many teardown videos showing engines with failed main bearings and little or normal debris present. It seems like that is what Toyota is now saying too. They saw the most obvious issue, debris, and stopped there. Then, the engines kept failing and they had to look again.