I’ve had a similar experience/problem with mine. It made it to 745k miles, but blew 3 cylinder sleeves about 2 weeks after DPF delete. Also, I’m being told that the Detroit DD15 motors are only lasting approximately 100k miles post rebuild. Apparently, Detroit is aware of this problem and unwilling to take responsibility for it. I’m told that following the rebuild of the motor, the lower rear bearings lock up. Has anyone else heard of this?