There's a good deal of A8 in the A6's genetics. It too makes extensive use of aluminium to help trim the weight. The bonnet, front bumper, bootlid and firewall are all constructed in aluminium, although such are the volumes that Audi predicted this car would sell in that an all-aluminium construction like the A8 would have proved too difficult to productionise. Despite being significantly larger than the previous generation A6, the weight of the MK3 2.4-litre saloon swelled by a mere 45kg to 1525kg.
The design isn't all show however. The neat integrated tail spoiler helps cut rear lift to a mere 19kg at 155mph. This represents a quarter of the outgoing model's lift and the drag coefficient has been cut too from 0.31 to a slippery 0.28. Despite its slinky profile, the tale of the tape doesn't lie and the A6 was launched as comfortably the biggest car in its class, dwarfing rivals such as the Jaguar S-TYPE and the Lexus GS series. The overall length swelled to 4916mm, up a whole 121mm over the outgoing car. The boot is a whopping 546 litres in all saloon models (or there's the Avant estate option) which is not only bigger than the equivalent BMW 5 Series and Mercedes E-Class but also manages to put this car's big brother, the A8, in the shade.
The MK3 A6 Avant features what has to be the most meticulously designed load bay in estate car history with all manner of hooks, eyes, hidden compartments, storage nets and so on. An optional reversible mat features velour carpeting on one side and a wipe-clean rubberised finish on the other, additionally incorporating a pull-out protective sheet that extends over the bumper, preventing damage to the car's paintwork. A detachable ski or snowboard bag was developed for this derivative, as was an internal cycle rack system - we could go on but you probably get the idea already.
Audi would probably be mortified had a car with this much development budget behind it developed any significant faults. It's all been quiet so far with no major recalls to report either. When buying, look for cars with leather and metallic paint and don't pay over the odds for optional extras such as satellite navigation. The ride on the A6 is rather firm, so watch out for this if the car you're looking at has the optional larger alloy wheels.
The complexity of the car should be enough to ensure you insist on an A6 with a cast-iron service history and, at this stage, Audi dealers are still likely to have the best examples. The premium they charge may be well worth your peace of mind.
Interiors are hard wearing and well designed, much like the rest of the car. As for corrosion, with an Audi you're pretty safe and there's a lengthy anti-perforation warranty to reassure you (ensure any conditions have not been breached by previous owners).
(based on a 2005 2.0 TDI SE Saloon - ex Vat) A clutch assembly is around £150. Front and rear brake pads should be about £65 a set. A radiator is about £140, an alternator about £235 and a starter motor £160.
Driver enjoyment is a key feature of the A6 line up and the car benefits from a quicker steering rack while retaining current suspension settings, albeit with fifteen per cent more travel. Existing A6 drivers won't recognise the feel behind the wheel and they can be excused for not feeling instantly at home with the interior. Although much of the look and feel is reminiscent again of the A8, the dashboard features a binnacle and centre console that angles towards the driver and is quite unlike anything yet seen in an Audi. The quality of the cabin remains top notch but there's a little more style and colour contrast here, Audi finally recognising that the coal hole dark plastic look was just that little bit too nineties to cut it these days.
Gone are the days when base specification A6 models were fitted with puny engines. This did Audi's image no good and the Mk3 model only has two four-cylinder engines: they are a grunty 138bhp 2.0-litre TDI turbodiesel and a 168bhp 2.0-litre FSI Turbo. Other than that, the line-up consists of V6 and V8 units exclusively, opening with a 2.4-litre 177bhp V6. Next up are 180bhp 2.7-litre and 225bhp 3.0-litre TDI turbodiesels. Then there's a 3.2-litre V6 FSI petrol engine that manages 255bhp. At the top of the range is a 335bhp 4.2-litre V8.
As usual with Audi, there are choices between front wheel drive and all-wheel drive Quattro variants and gearbox options extend to six speed manual, Tiptronic automatic and the Multitronic CVT. All models benefit from double wishbone front and multi link rear suspension, banishing the memory of the rather agricultural torsion beam rear axle that front-wheel drive A6 models have traditionally campaigned with.
The Audi A6 may not be cheap but it does offer a lot of car for your money. It's an easy car to get along with too, Audi making its high technology features accessible rather than infuriating. A used example is well worth a look and we'd plump for either the 2.0T or the 3.2FSI if going the petrol route and either the 2.0 or 3.0-litre engines if a diesel is preferred.