There are three basic reasons people buy Diesel powered trucks. They are: Economy, Longevity, and Towing Power

• Economy: Diesel engines can out perform gas engines doing the same jobs. They get up to 50% to 100% better fuel economy. The extremes would be when you compare carbureted engines to diesels. When both engines are put under heavy towing chores the diesel engines fuel economy becomes even more pronounced. A bonus is that diesel engines don't normally ever need tune ups. There are no points, spark plugs, wires or ignition distributors. A well maintained diesel engine can easily last 400 to 900 thousand miles. Gas engines pale in comparison. There is a good reason the trucking industry uses diesel motors exclusively.
• Longevity: Almost all diesel engines are built for commercial purposes. As result they are built tougher and stronger than gas motors basically designed for the consumer market. As commercial engines they are subjected to extremes as a result they are designed extremely tough. Diesels motors are tough and will last you a long time.
• Towing Power: Diesels and gas motors perform their towing functions differently. Diesels have tremendous torque. A diesel engine will tow huge amounts of weight and not generate nearly as much heat as a gas motor does when subjected to the same load. Diesels produce huge amounts of power at a much lower RPM than a gas motor has to attain the same amount of torque. At higher altitudes diesels are unaffected for the most part because they are turbo charged. On the other hand gas motors used in towing applications today are not and as a result loose a considerable amount of power as a consequence.
  
  
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