Some day, all-electric vehicles may rule the roads, but until then, manufacturers will continue to develop internal combustion engines, traditional drives and hybrid solutions in order to cut fuel consumption and CO2 emissions without sacrificing comfort and driving dynamics. At the centre of it all is the transmission – and the more complex the vehicle concept, the more complex the transmission technology.
Is the manual transmission out?
Germany’s drivers are increasingly letting their cars shift gear for them. At the turn of the century, manual transmissions accounted for 85 percent of the German market. Currently, 28 percent of cars on the road here have automatic transmissions, a figure that rises by a percentage point every year. Across Western Europe, the percentage of cars with automatic transmissions is rising, too. ZF is benefiting from the growth in automatic transmissions: at the Saarbrücken plant, which caters mainly to the European market, 1.05 million automatic transmissions have come off the lines. At the Chinese site in Shanghai, a further 71,000 are made for the local car market. In Brandenburg, alongside manual transmission, ZF is producing the new 7-speed dualclutch transmission.
Dual-clutch transmissions are gaining ground
Especially the market of dual-clutch transmissions is a rising market. The market research institute Global Insight predicts a 3 percent global market share for dual-clutch transmissions by the year 2012. But according to today’s figures for Germany and Western Europe the market share achieved by dual-clutch transmissions has not been achieved at the cost of traditional automatic transmissions. Automatic transmissions can peacefully co-exist alongside the new dual-clutch transmissions because they offer other advantages, too.
Dual-clutch transmissions perform well at revolutions over 8000 rpm, which is a major advantage. We install them as part of our own lines in sports cars where high revs are the norm,” says Dr. Gerhard Wagner, responsible for the ZF Car Driveline Technology division. By comparision automatic transmissions are lighter and have fewer components than dual-clutch transmissions, which, together with lower costs per unit, reduces overall production costs.
Ready for the hybrid age
ZF’s latest automatic transmissions are already equaling or improving on fuel consumption and acceleration statistics for manual transmissions. Production starts in 2009 on the state-of-the-art 8-speed automatic transmission which uses 6 percent less fuel than the already economical 6-speed version. These economies of scale will stay even if, as seems likely, the segmentation of the passenger car transmissions market continues. This is because the new 8-speed automatic transmission is constructed on a modular basis. Since it is thebase unit for both all-drive and all-wheel lines as well as hybridlines, ZF’s new automatic transmission flagship can be deployed without modifications on the basic transmission lines for micro-hybrids with crankshaft starter generators as well as complete hybrids. In short, it can cope with anything the developing hybrid market throws at it.
