Used Audi A6 Buying Guide
As Audi’s full-size executive car, the A6 majors on refinement: a hushed cabin, a long-legged motorway gait and, in Avant estate form, serious luggage space. Used buyers in the UK are mostly choosing between the C7 generation (2011-2018) and the technology-laden C8 (2018 onwards), with the rugged allroad version sitting alongside both. Depreciation has always been the A6’s quiet gift to second owners — these cars lose value quickly when new, which means a lot of luxury for the money secondhand, provided you buy a cared-for example.
Engines and trims
Diesel built the A6’s reputation. The 2.0 TDI — especially the economical “ultra” version of the C7 — is the sensible high-mileage choice, while the 3.0 TDI V6, in single- and twin-turbo forms, delivers effortless performance with respectable economy. Petrol options centre on the 2.0 TFSI (45 TFSI on the C8) and the potent 55 TFSI V6, and the C8 adds 48-volt mild-hybrid assistance across much of the range plus 50 TFSI e plug-in hybrid versions. Automatics dominate: S tronic or Tiptronic on most cars, and the Multitronic CVT on front-wheel-drive C7s.
C7 trims run from SE and SE Executive to S line and Black Edition; the C8 line-up moves through Sport, S line, Black Edition and the lavish Vorsprung, which brings air suspension and Matrix LED headlights. Well-optioned cars with the Technology Pack, upgraded sound systems or adaptive/air suspension are worth seeking out, as those extras cost a fortune new and little used.
What to check before buying
Early C7 diesels fall into the EA189 emissions-recall era, so establish whether the fix was applied and whether the car has run faultlessly since. All modern A6 diesels carry a DPF and, on later cars, an AdBlue system — a car that has done mainly short urban trips is a poorer bet than a motorway cruiser, so check for emissions warning lights and confirm the AdBlue tank and injector behave. Front-drive C7 automatics use the Multitronic CVT: any shudder, whine or hesitation is a deal-breaker, and service records should show transmission oil changes.
On the C8, make sure the 48-volt mild-hybrid system starts and coasts smoothly with no battery warnings, and that both touchscreens are responsive and free of dead pixels. Where air suspension is fitted — allroads and Vorsprung cars especially — watch the car raise itself on startup, look for a sagging corner after it has been parked, and listen for a laboured compressor. Check big alloys for kerbing and uneven tyre wear, and insist on complete service history; these are complex cars that reward disciplined maintenance.
Running costs
For its size, an A6 diesel is impressively cheap to fuel, with the 2.0 TDI ultra capable of small-car economy on a run. The V6 petrols are the thirsty choice, and plug-in hybrids only make financial sense with regular home charging. Insurance sits in the upper-middle groups, rising sharply for V6 and Vorsprung cars. Servicing costs more than a mainstream large saloon — budget particularly for gearbox oil changes, air suspension components on equipped cars, and premium-size tyres — but a good independent Audi specialist takes much of the sting out.
Verdict
The A6 delivers limousine refinement at family-saloon money on the used market, and the Avant remains one of the classiest load-carriers around. A post-2014 C7 ultra or a C8 40 TDI Sport with full history offers the best blend of economy and equipment; approach short-journey diesels, tired Multitronics and unserviced air suspension with caution. Buy well and it is a deeply satisfying long-distance car.
Browse more used Audi models.