2003 Cummins 5.9 with over 600,000 on it. How can I tell if the motor has been overhauled? It all looks factory but I find it hard to believe that it is original. Any ideas would be appreciated?

 

Paper work, thats proably one of the only ways you can tell if it has been...

 

Oil anaylis or drop the pan and inspect a rod bearing! If it was a one owner truck all highway miles probably still has a bit of life left in it! Besides consumable parts like injectors CP3 water pump etc etc the main engine should be good to go!

 

My buddy has a 98.5 cummins with 1 200 000kms and the motor has never be touched, just regular maintenance. So yours might not have been overhauled,