Diesel powered vehicles have never been popular in the US, despite previous attempts to promote this technology by leading manufacturers. Indeed, many motorists recall GM's failed bid to market diesel engines during the late 1970s to mid 1980s as a big reason to stay away from diesels. As you may recall, GM had to recall and replace the engines as they were plagued with crankshaft bearing problems. Many motorists cited other problems too including, blown head gaskets, warped heads, and bad fuel injectors. A well publicized class action suit against GM shut down the company's diesel program and resulted in GM replacing thousands of diesel engines with gasoline engines. Despite the earlier problems, many automakers are now poised to offer diesel engines as engineering changes have made diesels much more reliable and environmentally friendly.

Let's take a look at the diesel engines powering current and future vehicles traversing America's highways.Mercedes Diesels ? With five diesel models offered, Mercedes is leading the way. Its 3.2L 24-valve inline-6 diesel engine powers the E320, resulting in fuel savings of up to 30% and lower greenhouse gas emissions.Dodge Trucks ? Cummins has been producing turbo diesels for Dodge Ram trucks for years. The current 610 model offers best in class horsepower, excellent torque, and terrific towing capacity.

Jeep Liberty ? Using Mercedes technology, the Jeep Liberty common-rail diesel powering some models helps to boost torque by 45% and bump up fuel mileage by about one third. The Liberty diesel has been a strong seller for the Jeep brand.Volkswagen ? Mentioning "diesel" and omitting "Volkswagen" would be a travesty.

Indeed, the German automaker is one of the largest producers of diesel engines in the world.For the U.S. market, a 1.

9L four cylinder powers the cars while a humongous ten cylinder diesel can be found in the Touareg, the automaker's luxury SUV.Honda ? New to the game, Honda is promising that diesel versions of several of its cars will be made available by 2009. Along with its hybrid emphasis, Honda is pushing diesels to bolster its already well earned "green" image.

BMW, Range Rover, Ford, GM, and Chrysler all offer diesels although with the first two they are only sold in Europe. Ford taps Navistar for its big diesels while GM uses Duramax, a joint venture between it and Isuzu.Smaller diesels have yet to grab hold, but that may all change.Talk of smaller, lighter diesels built for American cars have been circulating for years with joint ventures involving Isuzu, Honda, VW, and Mercedes mentioned as possibilities.Demand for diesels is increasing as fuel prices continue to surge.

Auto registration records are indicating that diesel purchases have doubled in the past five years alone. With cleaner technology in place and all of the kinks worked out, consumers can be expected to demand diesels in greater numbers. This is good news for those who are concerned about America's over dependence on foreign oil.

By: Matthew Keegan