Volvo vehicles are equipped with the optional Geartronic transmission that permits the driver to select a gear using a steering wheel paddle-shift operated by the thumbs and without the aid of a clutch. The Geartronic essentially is a manual transmission without using the floor-mounted clutch. The Volvo Geartronic is similar to the Porsche Tiptronic transmission introduced in late 1989.
Background
Automakers have experimented with clutchless semi-automatic transmissions since the 1930s when Packard, Chrysler and Oldsmobile developed semi-automatics. More recent and far more successful examples of these types of transmissions are the 1990 and later Porsche 911 Tiptronic, the BMW Steptronic and the Chrysler AutoStick. Cars equipped with a manual transmission usually perform better than automatics, although the Geartronic comes close. Drivers allow engines to reach peak rpm before shifting gears with a manual transmission. Cornering and downshifting with a manual provides better control of the vehicle. Todays conventional automatics offer a lazier ride that requires no effort from the driver with the use of a computer-controlled automatic shifting system. The Geartronic offers drivers both options.
Volvo Geartronic
The Volvo Geartronic comes as a five- or six-speed version with a microprocessor chip to control shifting. In manual mode, the driver manually shifts the gearbox with the paddle shift. Shifting to automatic mode, the driver rests easy without worrying when to shift. In the manual shift mode, an instrument display panel tells the driver what gear the vehicle is using. By shifting to manual, the driver overrides the computers control of gear transitions and directly controls the transmissions torque converter. Manual shifting is especially helpful in downshifting to help brake the car. Volvos high-end models equipped with engines displacing 2 liters and more have the Geartronic as an option.
Volvo Manual Transmission
Volvo offers a conventional manual transmission with a clutch. The Getrag M66 has six forward gears and one reverse. The manuals gear ratios are a first gear 3:39-to-1 ratio, second 1.91-to-1, third 1.27-to-1, fourth 0.95-to-1, fifth 0.78-to-1 and sixth 0.65-to-1. In contrast, the five-speed Geartronic has a first gear ratio of 4.66-to-1, second 3.03-to-1, third 1.98-to-1, fourth 1.34-to-1 and fifth 1.02-to-1. The six-speed Geartronic features a 4.15-to-1 first, 2.37-to-1 second, 1.56-to-1 third, 1.16-to-1 four, 0.86-to-1 fifth and 0.67-to1 sixth.
Performance
Overall performance differences between Volvos six-speed Geartronic and six-speed manual are minimal. For example, the Volvo C30 equipped with six-speed Geartronic can reach zero to 62 mph in 9.5 seconds. The C30 with the manual achieves the same distance in 9.4 seconds. Top speed with the Geartronic is 127 mph, while C30s equipped with the manual is 130 mph. Theres a wider difference in fuel efficiency:The C30s manual version can achieve 55.4 mpg, while the Geartronic model earns 48.7 mpg.
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