are you serious???? I've put 70K on my silverado duramax diesel in 3 years as a personal vehicle just on vacations and other driving. (and 0 problems by the way) high miles/yr shouldn't have anything to do with engine problems as long as proper maintenance is done. with todays manufacturing processes and lubrications, ANY well designed engine should be capable of at least 200K miles without major problems.
You do realize that that was a joke. Of course a normal engine can go that many miles! But inside a Chrysler product? Maybe not. Also, Dmax is one best consumer grade Diesels on the market today. I'm not at all shocked to hear that is hasn't let you down.