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Volvo has developed a new Powershift six-speed gearbox that uses twin wet clutches and aims to provide the gearchanging comfort of a fully automatic transmission with the performance of a manual gearbox.
The engineering concept is similar to Volkswagen's Direct Shift Gearbox.
Operating as two parallel manual gearboxes, Powershift has twin wet clutches that work independently of one another.
One clutch controls the odd gears and reverse, while the other handles the even ratios.
The two clutches operate alternately with one engaging while the other disengages.
This means that at the same time as the engine gets full power and maximum thrust in first gear, second gear is placed ready to be engaged. When second gear has been engaged, third gear is readied and so on.
The Powershift transmission can handle high torque levels and in principle has no limitations on choice of ratio. The version that Volvo is now launching is dimensioned to handle torque levels up to 450Nm.
In the European-market versions of the Volvo C30, S40 and V50 in which it is fitted, Powershift is mated to the 2.0-litre four-cylinder turbo diesel engine, which delivers 320Nm of torque.
