For every Porsche fan, the three letters ‘PDK’ carry a magical meaning. This could be partly because they abbreviate a complicated German term like ‘Porsche Doppelkupplungsgetriebe’. On the other hand, it is due to the seven speed dual clutch transmission technology behind it.
Porsche PDK Dual-Clutch Transmission
The PDK dual-clutch transmission is in principle an automated gearbox, which enables automatic gear changes without power interruption thanks to two sub-transmissions. The gears are either sorted automatically or selected by the driver via the shift paddles on the steering wheel or by tapping the gear lever. In contrast to conventional automatic transmissions with hydraulic torque converter, the transmission of the torque takes place via one of two clutches which connect two partial transmissions to the drive. While the driving force is transmitted to the wheels via a clutch and the first partial transmission, the next gear is engaged in the second partial transmission. When changing gear, one clutch is opened, the other closed simultaneously. While one of the partial transmissions carries the even gears, the other takes the odd ones. The gears are already engaged when shifting, so that the traction is not interrupted when changing gear. This principle allows, like in an automatic transmission with hydraulic torque converter, a gear change in milliseconds.
The first six gears of the PDK have a sporty gear ratio, which means that the maximum speed is reached in sixth gear. In seventh gear, the long gear ratio lowers the engine speed, which optimizes fuel consumption.
The operation of the Porsche PDK largely corresponds to the handling of other fully automatic transmissions. The intervention of the driver is only required when driving off, reversing and parking. On request, the driver can also change the gears manually by using the shift paddles on the steering wheel or by tapping the gear knob.
In the 1980s, Porsche introduced the dual-clutch transmission for racing. The Porsche 956/962 was the first to be equipped with the PDK transmission, and thus achieved great success. With its 54 victories, the 962 is still one of the most successful racing sports cars Porsche has ever built. Since the technology and the computer capacities were still very limited, the serial development was not pursued at that time. In 2008, the PDK dual-clutch technology was transferred to the streets, and replaced in the Porsche 911 the previous automatic transmission ‘Tiptronic S’. At the time of its introduction, the PDK was up to 60 percent faster at shifting gears compared to other automatic transmissions. Following the Porsche Carrera, which was the first to get the new dual-clutch transmission in 2008, a year later the transmission was also offered with the Boxster and Cayman models.
One of the popular features of the Porsche PDK is the launch control. It enables optimal acceleration during start-up, preventing the tires from spinning through ideal power transmission. The engine speed is leveled for maximum drive without loss of traction.
☞ In 2011, the Porsche 911 991 introduced a 7-speed manual transmission based on the 7-speed dual-clutch transmission. The top speed is achieved as in the PDK in sixth gear, after which the seventh gear is used to save fuel.
The PDK transmission of the Porsche 911 GT3
In 2013, the PDK was improved in its speed and performance, and installed in its new version in the Porsche 911 GT3. In addition to lighter gears and wheelsets, which make the transmission about two kilograms lighter, it has shorter gear ratios. Unlike the usual PDK, where the seventh gear is used to save fuel, the GT3 reaches the top speed in seventh gear. The later model of the popular sports car was also offered on request of many enthusiasts with a newly developed 6-speed manual transmission. Although the PDK with launch control accelerates the GT3 by 0.5 seconds faster than the manual transmission to 100km/h, has shorter shift times, and is offered at the same price, many still choose the ‘slower’ manual variant. The good old manual transmission is not so easily beaten. With intermediate accelerations from low speeds on the circuit, in many cases it proves to be at least as fast as the PDK.
Porsche PDK vs Manual Transmission
An important question Porsche buyers often face is whether they should buy their car with PDK or manual transmission. For the hardcore purists nothing can replace the mechanical feeling you experience when changing the gears with a traditional shift knob. For others, the small bit of additional performance that the PDK offers is in the foreground. When it comes to launching, the manual can’t match the precision of PDK’s clutch control. Many do not care, because in this case you can not use your driving skills. However, you can’t go wrong with the precise PDK, which can also be operated manually in a certain way.
In the case of a used car purchase, the PDK can serve the buyer as an assurance for a durable gearbox. With a manual transmission there is always the risk that the teeth on the transmission cogs were worn out due to faulty gear changes.
It should be appreciated, however, that Porsche (still) offers its sports cars with a manual transmission. Maybe these are the last of their kind. Many other sports car manufacturers like Ferrari or Lamborghini have already discontinued these gearboxes, and only install dual-clutch drivetrains. This is partly because their clientele hardly chooses the manual option. Thus, the Porsche enthusiasts are the last of their kind who can still proudly carry out the gear change themselves.
☞ If you want to know how to pronounce ‘Porsche Doppelkupplungsgetriebe’ in German, you can watch it here: