Audi A6 C6

A6 at a glance

The A6 nameplate has been in use since 1994, and generations are designated by the codes C4, C5, C6, C7 and C8. A saloon and Avant estate are produced, while the allroad quattro is a raised-ground-clearance estate with air suspension. Sporty versions — S6 and RS 6. In 2025, a new internal-combustion-engined A6 generation was introduced, while the electric model is called the A6 e-tron.

The A6 is most often chosen for its spacious cabin, large boot (especially in the Avant), motorway quietness and quattro drive. Many imported cars are richly equipped, but complex systems — air suspension, matrix headlights, V6 engines — also mean more expensive repairs.

C7 and C8 — how they differ

The C7 (2011–2018) has a lot of aluminium in its body, making it lighter than its predecessor, while the cabin features the MMI system with a rotary controller. The 2014 facelift brought more economical engines and the option of matrix LED headlights. It is the most popular and most affordable generation on the used market.

The C8 (from 2018) stands out for its digital cabin: two touchscreen MMI displays, often a virtual cockpit instrument cluster, and more driver assistance systems. Most engines use a mild hybrid system (MHEV), and later plug-in hybrids TFSI e were added.

If price is the priority, choose a C7 after the 2014 facelift. If you want a modern cabin and newer safety systems, go for the C8.

Engines and gearboxes

In the C7 generation, the most common diesels are the 2.0 TDI (around 150–190 AG) and 3.0 TDI V6 (around 204–326 AG, including the twin-turbo BiTDI). Petrols — 2.0 TFSI, 2.8 FSI and supercharged 3.0 TFSI. Early front-wheel-drive cars' automatic gearbox is the continuously variable multitronic; after the facelift it was replaced by a 7-speed S tronic; quattro versions had S tronic or an 8-speed tiptronic.

In the C8 generation, the core of the range consists of the 35 and 40 TDI (2.0, around 163–204 AG), 45 and 50 TDI (3.0 V6, around 231–286 AG), 40 and 45 TFSI (2.0) and 55 TFSI (3.0 V6, around 340 AG), plus the 50 and 55 TFSI e plug-in hybrids.

C8 four-cylinder engines are paired with a 7-speed S tronic, while V6 diesels use an 8-speed tiptronic automatic gearbox.

What to check when buying a used A6

In V6 TDI engines, the timing chains are at the rear of the engine, so replacing them is expensive — there should be no rattling when starting a cold engine. On diesel cars, check the DPF and EGR, and on the C8 generation also the AdBlue system.

The air suspension (standard on the allroad, optional on others) should not sag after standing overnight, and the compressor should not run for long. The multitronic gearbox should work without juddering or whining; test the S tronic by pulling away from a standstill — some early C8 owners complained of sluggish pull-away.

The extensive electronics — MMI screens, cameras, lights and assistance systems — should work without faults; ideally, the car should be checked with diagnostic equipment before purchase. Check mileage against service and inspection records.

Trim levels

Names and equipment vary by market and year; in the C8 generation, trim lines were renamed, so we list those most commonly found in Europe.

Comparison of C8 generation versions

For most buyers, the best choice is an Avant with the 40 TDI or 45/50 TDI engine and advanced or S line trim. Allroad quattro is worth choosing only if you really need extra ground clearance and are prepared for air-suspension upkeep.

Frequently asked questions