300,000 ZF-Ecomat Transmissions for Bus and Rail

In July 2007, ZF produced the 300,000th Ecomat transmission. The ZF-Ecomat automatic transmission, which is not only used in the bus sector but has meanwhile also established itself in the rail sector, was first launched in volume production 27 years ago.

In those days already, the transmission system was designed in such a way that it was possible to adapt it quickly to technological or legal changes. Since 1980, the ZF-Ecomat has undergone four major development stages, and with every modification it became more powerful and more economical. Meanwhile it features 6 gears instead of 4 like at the beginning.

New emission standards, technological progress, and the demand for more economic efficiency – since the first generation, the Ecomat range has been adapted time and again to changing requirements. And in fact, it did so successfully! Today, ZF’s most important customers are Mercedes, Setra, MAN, Neoplan, Volvo, Irisbus, and Scania, mainly based in Western Europe. “They are joined by more and more bus brands from China, Japan, Korea, and North America”, states Wolfgang Schilha, Senior Vice President of the Bus Driveline Technology Business Unit at ZF Friedrichshafen AG. ZF produces the Ecomat transmission in Friedrichshafen and in Brazil.

The start of high volume production in Friedrichshafen in 1980 laid the foundation for this success story. Back then, ZF already offered the Ecomat transmission in three different performance classes and featuring four or five gears. The automatic transmission, which was mainly designed by ZF for city and intercity bus applications as well as for coaches, basically consisted of five components: converter, retarder, planetary gear set, control hydraulics, and automatic control unit. However, right from the start, the ZF-Ecomat was also used in rail vehicles as well as municipal, fire department, army, and construction site vehicles.

The sales figures of the ZF-Ecomat increased considerably in the following years. So in 1988, when it was technically revised for the first time, the automatic transmission was already well established on the market: Shifting processes and diagnosis were then controlled electronically.

Further adaptation became necessary when the Euro emission standards were introduced in the nineties. In 1998, ZF presented a completely revised version, the Ecomat 2: The new transmission featured CAN technology, new control electronics, and an electronically controlled CityBus retarder.

Only four years later, in 2002, ZF presented the Ecomat 2 plus. Self-learning electronics optimized both the shift quality and fuel consumption. A sixth speed was introduced with the slogan "6 in the City", thus contributing to further fuel savings in city and intercity traffic.

The most recent development stage of the transmission range is the Ecomat 4. The youngest Ecomat family member excels thanks to its increased input torque of up to 1,750 Newton meters and an additional cooling unit with optimized performance. An optional torsional damper in the converter and a modified neutral shift mechanism (during vehicle standstill) further contribute to considerable fuel savings.