Torque converter autos offer very smooth but not necessarily lightning quick gearchanges, earning them the affectionate name of ‘slushbox’ in some cases. That reputation is changing though, largely thanks to brilliant torque converters like the ZF 8-speed auto, which is fitted in dozens of performance cars from BMWs to Jaguars.
Dual-clutch gearbox
This type of gearbox is given many names by different manufacturers – Volkswagen calls it DSG and Porsche PDK, for example – but the principle is similar across different brands. A dual-clutch system operates with two clutches, as the name would suggest. One clutch handles odd-numbered gears and the other handles even numbers, and the two work in tandem to give amazingly fast gear changes.
On the move, twin-clutch automatics are smooth, quick-shifting and can even better their manual rivals for fuel economy and emissions. However, for pure city driving they can be jerky, and should they go wrong they’re very expensive and difficult to repair.
CVT automatic (Continuously Variable Transmission)
A different choice altogether is a CVT or Continuously Variable Transmission. Pioneered by DAF in the 1950s, these use belts rather than gears to provide a single variable gear, allowing for seamless ratio changes. Economical and cheap to repair, these types of gearbox are best avoided by keen drivers as they can give a somewhat disconnected feel to the car – as well as being noisy under load.
Automated manual transmission
Rounding things off is the automated manual transmission. These transmissions use a regular clutch and gear set-up but robotise the action. They feature mostly in cheap city cars – for example, Smart used exclusively automated manual transmissions across the Fortwo range until the most recent model. They have the advantage of being cheap, lightweight and simple – but are often jerky around town and under hard acceleration. They’re often best avoided, and you won’t find any in our top 10 list.
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Now check out our list of the best automatic vans…
