New Audi A6 - In Depth

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Audi

Transmission

The decision to fit the new Audi A6 as standard with either a manual six-speed gearbox or six-speed automatic transmission with a wide range of gear increments serves to optimise both fuel economy and the car's superior driving dynamics.

Six gears featured as standard

The manual versions of the new Audi A6 come with Audi's new generation of ML transmissions, the abbreviation ML standing for Manual/Lengthwise.

Featuring tight gear increments, this sophisticated gearbox of the latest generation combines extreme precision in shifting gears with short, clearly defined gearshift travel. The special gearshift fork mounts, in turn, effectively disconnect the gearshift lever from vibration in the process of power transmission, without the driver being disturbed by even the slightest "tremble" affecting his hand on the shift lever.

The reduction of internal friction by a number of improvements helps to optimise the standard of efficiency, with the transmission converting engine power into drive forces even better and more smoothly than ever before.

Six-speed tiptronic

Six-speed tiptronic transmission is available in conjunction with the very high-torque 4.2 V8, 3.2 FSI, and 3.0 TDI power units featuring permanent four-wheel drive. Having already made its debut in the Audi S4 high-performance athlete, this transmission converts the power and muscle of the engine into a superior symbiosis of dynamism and running smoothness.

Weight reduction, a fast and crisp gearshift, as well as optimised gear strategies help to combine the superior comfort of automatic gearshift with the sporting performance so typical of the A6.

Compared with its five-speed predecessor, the new six-speed gearbox is 14 kilos lighter, overall weight of the transmission being a mere 115 kilos.

Again compared with a five-speed automatic transmission, the overall range of gear increments is up by 18 percent on average. This means far better acceleration at low speeds and a significant reduction of engine rpm at high speeds. And this, on the road, means a reduction in both the noise level and fuel consumption.

A further advantage of the new six-speed tiptronic transmission is the much faster gearshift. The driver benefits from this greater spontaneity particularly when shifting down, agility being further enhanced by automatic double-declutching between gears.

Both in stage D and in the S sports program the electronic control unit responds efficiently to parameters such as lateral and longitudinal acceleration as well as the driver's movement of the accelerator pedal. This helps to prevent any unwanted upshift of the transmission in bends.

Continuously variable multitronic

After making its debut successfully in the Audi A6 in the year 2000, Audi's continuously variable multitronic automatic transmission now also offers its superior qualities in the new A6, combining the benefits of a manual gearbox with those of a multi-stage automatic transmission. Fortes typical of multitronic are smooth but very dynamic acceleration as well as convenience in use and the efficient transmission of power.

The high standard of comfort and convenience offered by multitronic exceeds that of a conventional converter-type automatic transmission, while in terms of dynamic performance and all-round economy multitronic can by all means be compared with a manual gearbox. And if the driver wishes to actively choose the appropriate transmission ratio, he is able to do so conveniently by means of paddles on the steering wheel now providing no less than seven predefined gear ratios.

Numerous reinforcements and adjustments, as well as optimised cooling, serve to significantly enhance the all-round performance and qualities of Audi's continuously variable automatic transmission. The multitronic is now even able to convey torque of up to 330 Newton-metres, thus qualifying as an ideal partner even for the most powerful V6 engine in the series, the 3.2 FSI developing maximum output of 255 bhp and maximum torque of 330 Nm.

Modified for the new Audi A6, the so-called multitronic variator spans an even wider range of gear increments: the overall ratio between the largest and the smallest gear transmission ratio is now 6.25:1, virtually ideal for such a transmission. On the road, this means dynamic acceleration with the largest possible transmission ratio, while the smallest ratio helps to capitalise on the engine's potential in saving fuel.

A special feature of multitronic is its ability to emulate the particular functions and features of a manual gearbox. Introducing the latest version of multitronic, Audi has opted for no less than seven forward gears activated by the driver using the selector lever by means of a one-touch function in the second shift plane or by pressing down the gearshift paddles on the steering wheel (optional).

These seven gearshift stages are memorised by the system as regular shift programs. Depending on the stage chosen by the driver, the system activates the appropriate transmission ratio then duly set and maintained. Adjusting smoothly and consistently, these manual gearshift processes are always smooth and free of any jolts or bumps, no matter how sporty or dynamic the driver may choose to be.

A brand-new multitronic function in the Audi A6 is the start-off assistant: simply pressing down the brake pedal, the driver is able to activate the brake system automatically, preventing the car from rolling back on a gradient and then opening up again as soon as the driver opens the throttle when setting off.

quattro permanent four-wheel drive

quattro permanent four-wheel drive is a typical feature of all high-performance Audi models. The big advantage of quattro drive is excellent traction and side stability, with the influence of drive forces on the car's steering being reduced to a minimum. This, in turn, ensures very high speeds in bends as well as a high level of driving stability.

A Torsen differential in the new Audi A6 with the engine fitted lengthwise automatically distributes optimum brake power to all four wheels. Made up of the terms "torque" and "sensing", the acronym "Torsen" quite literally stands for "sensing the torque developed by the engine". The Torsen differential itself is a self-locking worm gear.

The big advantage of this differential is that it build up its lock effect only under drive power, the transmission allowing different speeds of rotation when applying the brakes and in bends.

Under normal conditions 50 percent of the engine's power goes to each axle, with 75 percent of the total drive power going to just one axle in an extreme case.

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