I have a 2014 Silverado 1500 with a 5.3. It currently has 308k miles I’ve replaced everything (not including the frame and body) except the brake booster and motor. The motor just sorta gave out, due to the dod/afm system. I have a spring that’s getting stuck when compressed it’s on cylinder 1 . I’d put money on it, if the dod system wasn’t installed on this my motor would still be going strong. I’m not the type to drive a truck easy I beat on it like a tractor so for the motor lasting this long, I give my ultimate respect to it. I’m rebuilding my motor and deleting the dod system hoping I can get another 300k out of it