Speaking of
oil,,,, and not wanting to start a debate that wanders off the original topic, your choice of
oil will have a HUGE bearing on how long an engine is protected. I have run Rotella T longer than I can remember and have NEVER had an
oil related failure. Most of your decent diesel spec oils are higher in good stuff than whatever else there is available. Take it for what it's worth but I personally have put over a million miles on various truck engines with NEVER an oil related failure.