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What’s it like?
The Audi A6 is the big, luxurious executive car that’s designed to take on the likes of the BMW 5 Series, Mercedes E-Class, Volvo S90, Maserati Ghibli and the Lexus ES, among more. This buying guide focuses on the fifth generation of the A6 history, which only went out of production as the A6 e-tron all-electric replacement arrived. With three body styles, a wealth of drivetrain options, and even two high-performance derivatives, there should be a ‘C8’ version of the Audi A6 to suit all needs.
Which model to go for?
Audi sold this A6 in three distinct body styles – the regular four-door saloon, the five-door Avant estate, and then the lifestyle, off-road take on the Avant with the name allroad quattro. Almost all A6s used quattro all-wheel drive, although some of the lowest-powered petrol and diesel models could be front-wheel drive. And take-up of manual gearboxes was so low on the preceding fourth-generation A6 that by this model’s turn in the limelight, Audi decided to make them all automatics: either seven-speed S tronic dual-clutch units, or an eight-speed torque-converter Tiptronic.
Power came from an array of turbocharged petrol (TFSI) and diesel (TDI) engines, ranging from 2.0 litres and four-cylinder units, through V6s and right up to a monster 4.0-litre biturbo V8. Some of the powertrains had mild-hybrid assistance to save fuel, and there were also plug-in hybrid options with the ‘TFSI ‘e badging.
Realistically, you can’t go wrong with any of these engines, as even the least powerful iterations had more than enough about them to deal with the A6’s shell, but be warned that something like, say, a 55 TFSI (a 340hp 3.0-litre V6 turbo petrol) is not going to be cheap to run. That’s also true of the two fast models, the S6 and the RS 6. The former is a little more realistic, with its 349hp TDI V6 diesel providing masses of torque and the potential for something like 8.0 litres/100km if you’re careful with it, but the RS 6 takes some ignoring – it has 600hp and supercar-like pace. Supercar running costs, too.
The allroad quattro wasn’t officially sold here, which is a pity as it was magnificent for ride quality and refinement, so if you see any on the used market, they’re likely imports. By far and away the most common model will be the 204hp 2.0-litre TDI, which is a perfectly proficient choice to go for if you want a fifth-gen A6.
Does anything go wrong?
There are issues with timing-chain swaps on the V6 and V8 engines at higher mileages, as Audi places them on the transmission side of the drivetrain so it’s an involved job when the work needs doing. There were also issues with the infotainment on the earlier examples, and the powered tailgate on models with it fitted (commonly on the Avant) can be problematic. Check all of these electrical systems work properly.
This generation of A6 was subject to eight recalls: two for airbags; one for the adjustment of the rear-axle toe/camber; one for stress corrosion of the rear-control-arm bolts; another for moisture potentially getting into the belt starter-generator on mild hybrids; one for the centre-rear seatback become unlatched; one for a defective trailer hitch locking mechanism; and the final one pertaining to the sunroof bonding in early Avant models.