Key to the changes is a range of new or updated four-, six- and eight cylinder engines – all claimed to offer added fuel efficiency and lower emissions for EU6 compliancy across the line-up.
They sit alongside revised gearboxes choices, some subtle styling tweaks and new entertainment system options.
Joining the A6 line-up are two fuel efficient "Ultra" models featuring subtle aerodynamic tweaks and a series of weight saving initiatives, including springs made of glass fibre-reinforced polymer (GFRP) on the diesel variant that save a claimed 4.4kg.
Based on the 2.0-litre four-cylinder direct injection petrol powered A6 1.8 TFSI and 2.0-litre four-cylinder common rail diesel propelled A6 2.0 TDI, the new "Ultra" models deliver respective fuel consumption and CO2 emissions of 49.6mpg and 133g/km and 67.3mpg and 109g/km in combination with an optional seven-speed dual clutch gearbox.
Further up the range, Audi has tweaked the 3.0-litre V6 common rail diesel used in the A6 3.0 TDI. In single turbocharged form, it now offers 215bhp or 268bhp.
The more recently introduced twin-turbocharged derivative of the engine has also been upgraded and now kicks out 315bhp in standard form or a more potent 341bhp in a pair of special-edition models. The new variants, dubbed the A6 3.0 TDI competition and A6 Avant 3.0 TDI competition, have been created to celebrated 25 years of TDI technology.
The new A6 3.0 TDI competition performance diesel runs a standard eight speed automatic gearbox. All other engine variants run either a standard six-speed manual or optional seven-speed dual clutch gearbox. The unloved multitronic continuously variable transmission has been dropped.
In A6 models with an engine output over 268bhp, Audi’s quattro four-wheel drive can be supplemented with a so-called sport differential, which aids traction by varying the delivery of power between each individual rear wheel.
In line with the recently introduced facelifted S7, the four-wheel drive S6 and S6 Avant now run an updated version of Audi’s twin-turbocharged 4.0-litre V8 direct injection petrol engine developing an added 30bhp, at 444bhp.
Official performance figures put their 0-62mph times at 4.4sec and 4.6sec respectively. Fuel consumption is a claimed 30.7mpg and 30.1mpg, corresponding to CO2 figures of 214g/km and 219g/km.
Among the subtle cosmetic changes made to the A6 are stylistic tweaks to the car’s single frame grille, headlamps, bumpers, side sills and tailpipes.