The ford 7.3L powerstroke turbo diesel is by far the best engine that was ever in production. The engine block it self will easily exceed 300,000 miles and still run great as long as it is taken care of. I have owned one for 11 years and never fixed anything internally on the engine. Simple maintenance like pulley's fuel lines and belts are expected. The newer powerstroke engines(6.0L) have all kinds of problems with blown head gaskets and melted O-rings anywhere over 50,000 miles, however these engines were probably modified with chips and programmers. The 7.3l may not have the torque and HP that newer diesels have but it is a reliable engine and will always get 2 thumbs up from me.