Choosing a gearbox for your vehicle used to be as simple as ticking either automatic or manual.
The manual market has stayed fairly static, probably because those systems are less complex and therefore less in need of experimentation.
Automatic gearbox systems are a different story. Efforts have been made to improve their efficiency and performance, leading to a number of innovations. This can make it tough to choose between them – that’s why we’ve put together a quick overview.
Traditional Automatic Gearbox
Traditional automatics use a torque converter to perform the same job as the clutch in your manual. It uses the resistance of hydraulic fluid to transmit drive from engine to gearbox, so shifts are made without your intervention. This usually happens with the aid of a computer, though some automatics also have a manual mode. They change gears more seamlessly than older units, but not quite as quickly as manuals or other automatics, which tends to make them in efficient.
Dual-Clutch Automatic Gearbox
Yep, this one comes with two clutches; one controls odd-numbered gears, and the other controls your evens. This means that the next and previous gears can be lined up while you drive. When you accelerate or decelerate, your car switches from one clutch to another in a snap, usually faster than a human could operate their manual. This makes them extremely efficient, but a slight delay when the first clutch engages makes for poor low-speed progress and manoeuvring.
Automated Manual Gearbox
The popularity of automated manuals has been somewhat eclipse by the rise of dual-clutch systems, but they’re still around. You’ll still have a regular manual gearbox, but there’s no clutch pedal. Everything is operated electronically. The car automatically disengages and then reengages the drive when a shift is required. These are more efficient than traditional automatics, but they lack the shifting speed and fluidity of other systems.
Continuously Variable Transmission (CVT)
CVT systems represent a whole new spin on transmission. Two pairs of metal cones hold a computer-controlled belt that moves them towards or away from each other. There aren’t actual gears – the gear ratio keeps changing according to current needs, hence ‘continuously variable’. It sounds odd and slightly rudimentary, but these systems are essentially always operating at an optimal gear ratio, making them the best of the bunch in terms of efficiency, and your progress will feel seamless since no gear changes will occur. However, some people dislike the way these systems sound, loud while accelerating and without the traditional rise and fall of a conventional gearbox.