Although it had been invented in 1890, the diesel engine was not common in trucks in Europe until the 1920s. In the United States, it took much longer for diesel engines be accepted: gasoline engines were still in use on heavy trucks in the 1970s, while in Europe they had been completely replaced 20 years earlier. They are the most commonly used trucks all over the world.
Trucks can use all sorts of engines. Small trucks such as SUVs or pickups, and even light medium-duty trucks in North America will use gasoline engines. Most heavier trucks use four stroke turbo intercooler diesel engines, although there are alternatives. Huge off-highway trucks use locomotive-type engines such as a V12 Detroit Diesel two stroke engine.
In the United States, highway trucks almost always use an engine built by a third party, such as CAT, Cummins, or Detroit Diesel. The only exceptions to this are Volvo Trucks and Mack Trucks, which are available with Volvo and Mack diesel engines, respectively, and Freightliner, a subsidiary of DaimlerChrysler, which are available with Mercedes-Benz and Detroit Diesel engines. Trucks and busses built by the Navistar International can also contain International engines. The Swedish truckmaker Scania claims they stay away from the US-market because of this third party tradition. Scania wants to sell a highly integrated product with proven interoperability and quality.
In the European union all truck engines must comply with Euro 4 regulations, the regulations will become more severe in 2008 with the introduction of Euro 5.
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