For every version of engine in the A5 family, Audi offers the perfect transmission – ranging from a six-speed manual transmission through a continuously variable multitronic to a sporty seven-speed S tronic. Regardless of the engine in question, the differential is in front of the clutch. This unconventional solution places the front axle very close to the vehicle’s front end, in turn allowing for a long wheelbase and an ideal distribution of the axle loads.
But there are more characteristics common to all A5 transmissions – such as high efficiency ratios thanks to low internal friction as well as smooth and precise operation. Moreover, the gear spread is wide: The narrow ratios of lower gears enable sporty driving, while higher ones are spread broad to reduce engine speed and boost fuel efficiency.
A manual transmission is standard for the 1.8 TFSI and the 2.0 TDI. Its overall weight is low and intelligent placement of the shift forks protects the shift lever against vibrations. An on-board computer with efficiency program, standard in the A5 model line, integrates a gear-change indicator for manual transmissions.
The silky smooth multitronic is a good match for the 3.0 TDI with 150 kW (204 hp). The multitronic is also available for the A5 Cabriolet featuring a 2.0 TFSI as well as the Sportback and Coupé with a 2.0 TDI. Irrespective of configuration, the multitronic distributes the engine’s power to the front wheels. This continuously variable transmission allows the engine to almost always operate at its optimum efficiency ratio. For dynamic drivers, there is a sport program and a manual mode with eight dedicated drive positions – and with shift paddles on the steering wheel available as an option.
At the core of the multitronic lies a variator. A link-plate chain transmits power between two variable V-pulleys, one of which is atop the driveshaft and the other on the output shaft. Their conical faces readily engage and disengage. In this way, the chain moves as per different radii and the transmission ratio changes in a continuously variable manner. An electronically controlled, hydraulic multi-plate clutch boosts the multitronic’s efficiency by uncoupling the transmission from the engine whenever the vehicle comes to a stop.
Lightning-fast shifting: Seven-speed S tronic
The sportiest transmission in the A5 family is the seven-speed S tronic, which is always paired with quattro permanent all-wheel drive. Audi will initially offer it in the 2.0 TFSI quattro – standard in the Coupé and Sportback, and optional for the Cabriolet. On the 3.0 TDI with 180 kW (245 hp) it is standard, as it will be with the 3.0 TFSI set to appear before long.
The seven-speed S tronic consists of two sub-transmissions, which are alternately actuated by two clutches. Gear-shifting is executed by this dual-clutch transmission; it lasts just a few hundredths of a second and is extremely smooth. The electronic control management has a fully automatic mode at the ready, with two types of operation: D (Drive) and S (Sport). The driver can shift whenever they wish, even via optional shift paddles on the steering wheel.
Audi will initially offer the 2.0 TFSI with quattro permanent all-wheel drive. It is standard in the Coupé and Sportback, and optional for the Cabriolet; as for the 3.0 TDI with 180 kW (245 hp), it is generally standard equipment. The quattro technology – which operates by purely mechanical means and therefore entirely instantaneously – ensures outstanding driving dynamics, traction, driving safety and straight-line stability.
The quattro technology has made Audi the premium segment’s most successful all-wheel-drive manufacturer in the world. In 2010 alone, the brand sold over 437,000 vehicles with a quattro drivetrain.
The heart of the quattro drivetrain is a self-locking center differential. Under typical driving conditions, it distributes a majority of the engine’s power to the rear for sportiness – 40 percent to the front axle and 60 percent to the rear axle. In the event of wheel slippage, the differential transfers a majority of the power to the other axle.
The mechanical center differential operates in conjunction with torque vectoring. This intelligent software solution will detect and respond if an inside front wheel is at risk of losing grip while the vehicle corners at a high speed. It brakes the wheel very slightly – almost imperceptibly – before this can happen, making handling even more fluid and traction even stronger.
With regard to the 3.0 TDI quattro, 3.0 TFSI quattro and the S models, a sport differential is available as a perfect complement. It actively distributes power between the rear wheels during high-speed cornering. This is accomplished by two superposition gears operated at lightning speed via multi-plate clutches. The system guides the A5 during high-speed cornering, as if the vehicle were on rails – with spectacular precision and traction.
The equipment and data specified in this document refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.