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If you own a truck with the 6.4 Powerstroke, chances are you’ve probably already encountered some or all of these problems. One of the main reasons for getting a diesel engine is that it can typically be modified to increase horsepower, and the 6.4 Powerstroke is no different. The 6.4 Powerstroke came after the 6.0 Powerstroke, which was widely panned for its problems and poor performance. The issues with both of these engines eventually led to the end of the working relationship between Ford and Nav