Ever increasing congestion of the roads means that cars fitted with automatic gearboxes are more appealing than ever. Better still, thanks to advances in technology, these labour-saving transmissions are often more efficient than a standard manual gearbox.
These days there are several different types of transmission to choose from – all will shift gears for you automatically, but they do it in very different ways. Most popular is the traditional auto, which uses a fluid coupling called a torque convertor to transfer power from the engine to the gearbox.
Many manufacturers now offer a twin-clutch set-up, which promises unrivalled smoothness and double-quick shift times. Essentially this system splits the gearbox in two, with each half getting its own electronically controlled clutch. The benefit of this set-up is that the gearbox can pre-select the next ratio, resulting in virtually seamless changes.
For smaller cars, manufacturers often favour a Continuously Variable Transmission (CVT). By employing a pair of belt or chain-linked pulleys, this system can deliver smooth acceleration and a theoretically infinite amount of ratios, which promises to be good for both performance and efficiency.
Finally, some firms use low-cost automated manual units. By combining a standard manual gearbox with an electro-hydraulically operated clutch, these systems deliver automatic shifts for a fraction of the cost. However, they are often jerky and unresponsive, making them frustrating to drive.