Dual-clutch gearboxes and continuously variable transmissions are gaining in popularity, but which of the two systems will ultimately prove the most popular alternative to the "stick shift"?
Dual-clutch gearboxes (such as DSG - offered on the Volkswagen Golf 5, Audi A3) and continuously variable transmissions (available in the Fiat Palio, Mini Cooper, Audi A4 and A6, Honda Jazz and Toyota Prius) are gaining in popularity, but which of the two systems will ultimately prove the most popular alternative to the "stick shift"?
"The dual-clutch transmission will put the final nail in the coffin for the CVT in Europe", Andrew Fulbrook, manager of European powertrain forecasts at CSM Worldwide, told recently.
However, Coen van Leeuwen, head of product planning at Van Doorne Transmissie, was more philosophical on the subject: "The industry is at a crossroads to make long-term choices between CVT and dual clutch".
Volkswagen AG is said to be driving the growth of the dual-clutch transmission. The Wolfsburg-based company's chairman Bernd Pischetsrieder recently said 11 per cent of the Golfs sold in Western Europe were equipped with DSG.
"VW started and now everyone is following, everyone is doing it (adopting dual-clutch transmissions," Fulbrook was quoted as saying. "They might not all go into production, but they are all doing it."
Fulbrook thinks the CVT (an automatic transmission that uses a belt or chain to connect two pulleys that slide on shafts and vary the gear ratio based on engine speed) will disappear in Europe from all but the Japanese brands because of cost.
A dual-clutch transmission is a manual transmission with the option to drive in automatic mode. Some consider it part of the automated manual transmission family because it allows drivers to either set the transmission as an automatic requiring no manual shifting or lets drivers manually shift without depressing a clutch pedal.
Some European manufacturers have already shifted to automated manual transmissions for their small-segment cars... Automated manual transmissions are smaller, lighter and cheaper to produce than CVTs.
A disadvantage of dual-clutch transmissions is that, because of low volume, it costs more to make than most manual transmissions. But it still costs less to produce than a CVT with a chain and therefore
CVT producers have fewer economies of scale.
ZF Friedrichshafen chief executive Siegfried Goll said the German supplier was counting on Japanese companies to promote CVTs.
"We have had a difficult time implementing the CVT concept in the US and Europe, while in Asia, we've seen a completely different situation emerging," Goll said last year.
ZF expects that just one per cent of the cars produced in Western Europe will be fitted with a CVT by 2012 (the same level as in 2002). By comparison, ZF forecasts that production of the dual-clutch transmission will rise to six per cent by 2012.
Globally, Nissan has sold more than 1 million vehicles equipped with CVTs, says Kurt von Zumwalt, director of product public relations at Nissan North America Inc. He says Nissan expects a fourfold increase in global CVT applications during the next three years.
Both dual-clutch and CVT transmissions are more fuel efficient than automatic transmissions (all things being equal). However, the dual-clutch transmission is less expensive to make than a CVT, because it can be built on the same assembly line as a manual transmission.
also reported that some CVT units are shorter and taller than gearboxes, and, because CVTs are rarely the only transmission offered for a vehicle, engine bays need to be designed to accommodate both types, which adds to development costs.
BorgWarner has booked sales of about R1,81 billion of its dual-clutch modules through 2007, the company's chief executive Timothy Manganello said. That represents about 20 per cent of the sales it has booked for 2005 until 2007, the report said.
Original article from Car