Semiautomatic transmissions have gained popularity in the last 10 years. The manufacturers of family cars and high-end exotics all make vehicles with semiautomatic transmissions. This transmission type is expected eventually to replace nearly all standard manual transmissions.

Function

A semiautomatic transmission uses computer electronics to engage the clutch and execute gear shifts at the driver's command, without the use of a clutch pedal. The system was designed to ease driver comfort (especially in congested cities) while retaining the feel of the traditional manual transmission.

Operation as an automatic

Most semiautomatic transmissions have the ability to operate as a full automatic, requiring no gear shifts from the driver. This frequently happens when the driver is redlining, or reaching the maximum safe engine speed, and the computer shifts automatically to prevent damage to the vehicle.

Pros

The semiautomatic transmission is easier to use than a standard manual due to the elimination of the need to press a clutch pedal. Semiautomatic transmissions are also more precise and can shift faster than any person could. The computers also prevent the car from stalling.

Cons

Some driving purists argue that the automated shifting takes away from the driving experience. Because the system is controlled electronically, semiautomatic transmissions are more prone to electronic failure, though the technology used in today's vehicles is extremely advanced. Also, vehicles with semiautomatic transmissions usually cost more than vehicles with manual transmissions.

Naming

Each car maker make uses a different marketing name for its semiautomatic transmission. This can make the process of identifying a true semiautomatic---as opposed to a Tiptronic or manumatic---transmission more difficult for the consumer.

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Semiautomatic transmission

Leading Transmission Maker Predicts Major Shift to Automatics in Heavy Vehicles