Audi A6
Audi made a high-performance, 4.2-litre V8 engine (parts code prefix: 077, identification code: AEC) with a Bosch KE-Motronic ECU available as an option in the original European S4s, and made the decision to continue to do so with the S6, making a version of the 4.2 available as an optional upgrade over the 2.2-litre inline five-cylinder turbo. Unlike the five-cylinder turbocharged version, the V8-powered S6 was supplied with a four-speed automatic transmission as standard, but kept the quattro four wheel drive. A six-speed manual gearbox was also available as an option.
Multitronic
Multitronic was offered on front wheel drive-only versions of the Audi A4, Audi A5, Audi A6, and the SEAT Exeo with the 2.0 TSI gasoline engine. It is not compatible with the quattro four-wheel drive system, nor transverse engine installations such as in the Audi A3. At first, the torque limit was , but the transmission is now modified to withstand torque. In 2014 Audi announced to discontinue Multitronic and replace it with S tronic, effectively making the Audi A5 8T the last model it was sold with.