The 7.3 power stroke was designed to be a million mile motor . I have been in the ambulance business for 25 years . The 7.3’s are the only motors we NEVER had a failure with and that’s saying a lot as we are hard on equipment lol they truly outlasted the ambulance body’s. We have had many blowed ford 6.0’s,6.4’s and a couple of new 6.7’s