The long and intensive testing route leading to Euro VI

The extensive and intensive development and testing work Daimler Buses performs with Mercedes-Benz and Setra is apparent in the key development steps leading up to the introduction of the new vehicle generation with Euro VI engines.

Intensive tests in icy temperatures were also necessary for the early and comprehensive introduction of Euro VI. After all, it is not just a new and highly sophisticated engine generation that is being used in the Mercedes-Benz and Setra buses. To maximise economy, an all-new powertrain layout and package was developed for Euro VI, both for the touring coaches and rural-service buses with raised floor and for the low-floor urban and rural-service buses.

This was one of the focal points of advance bus development from as early as 2004, a full ten years before Euro VI became a legal requirement. Two years later, the first buses of the current generation with Euro VI engines were already on the road in "test mule" guise. All-new Euro VI prototypes were ready for the off in the first half of 2008. Mercedes-Benz and Setra were the first brands to put these test buses on the road. Between 2007 and 2013, the new vehicle generation completed seven years of extensive winter and summer testing.

The end products of these tests are exceptionally well-engineered and economical solutions for transport operators and private companies. The Mercedes-Benz Citaro and Travego models - the first urban bus and touring coach to feature completely newly developed Euro VI engines - went into production at the same time. A total of around 60 prototypes, including 26 buses for endurance testing, underwent road testing in preparation for the changeover to Euro VI. Together they covered more than five million kilometres.These trials involved 42 test engineers, 33 mechanics and a large team of drivers, notably for the endurance tests.

Winter tests played an important role in this context. The newly designed engine compartments with their precisely calculated airflow were put to the test in sub-zero temperatures in Lapland. It was possible to test exhaust gas emission control on real urban regular-service routes with the critical mix of low load and extremely low temperatures.