Drivetrain

The new Audi A8 offers the utmost superiority also in power transmission. All engine versions have a new, electronically controlled 8-speed tiptronic system and quattro permanent all-wheel drive from the production line. On request, Audi also installs the dynamic sport differential, standard with the 4.2 TDI quattro.

The 8-speed tiptronic is a totally newly developed automatic transmission. Its great strength lies in the high overall gear ratio of 7.0:1 between the shortest and longest gear ratio, reducing the fuel consumption by about six percent. Starting off, the A8 accelerates dynamically, rolling along highways with low, consumption-reducing revs. All gear changes are nearly unnoticeably soft and smooth, very fast and highly flexible.

The 8-speed tiptronic achieves a high level of efficiency. One of the factors behind this is the highly efficient pump for supplying oil, another the heating of the oil by the coolant following a cold start, for lowering frictional loss. In interplay with the 3.0 TDI a hydraulic accumulator is on board to ensure start-stop functionality. For the restart, its oil volume is pressed into the system by spring pressure – meaning that the tiptronic is ready to start in no time.

The dynamic shift program (DSP) that controls the transmission features the automatic operating modes D and S. A pioneering innovation from Audi is its networking with the detailed route data supplied by the optional MMI navigation plus system. By means of this data the DSP incorporates upcoming curves in its gearshift strategy – it avoids unnecessary gear changes on narrow roads, for example.

The new selector lever on the center tunnel is for selecting driving modes – shaped like the thrust lever on a yacht, it forms a highlight in the elegant interior of the sedan. The ergonomically perfected lever communicates with the transmission electronically. Gear changes are triggered by a brief tap of the lever, after which it automatically returns to its center position. You can also change gears using the rocker switches on the steering wheel.

The installation position of the new tiptronic follows a special layout – as in many models from Audi: The differential lies in front of the torque converter. The front axle is then moved forwards – the advantages are a long wheelbase, a short front overhang and a finely balanced weight distribution.

The quattro permanent all-wheel drive system equally contributes to the new A8’s leading position. Its mechanical center differential manages normal automotive operation: 60 percent to the differential of the rear axle and 40 percent to the front – a sporty characteristic. Should slip occur at a wheel, the differential sends the large part of the torque to the axle with the better traction.

Customers with a particularly sporty driving style may decide on the optional sport differential with its continuously variable distribution of the drive forces between the rear wheels ­– standard on the 4.2 TDI quattro. With the sport differential the A8 drives as if on the proverbial rails.

The sport differential’s controller is connected to the Audi drive select vehicle dynamics system. The driver can switch between the system’s three characteristics – auto, comfort and dynamic – at any time.

The equipment, data, and prices specified in this document refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.