AUDI A6 DIESEL AVANT S6 TDI Quattro Vorsprung 5dr Tip Auto

Audi rejuvenates its big A6 Avant estate - for those who don't want an EV. Jonathan Crouch takes a look.

Ten Second Review

Audi proves that - for the moment - it also remains committed to combustion power, at least with this car, the rejuvenated C9-generation A6 Avant. It's not the most practical large premium badged estate you could choose, but it's the sleekest, possibly the smartest and certainly the nicest to sit in.

Background

You might not expect the most aerodynamic combustion model Audi has ever made to be a big A6 Avant estate, this six generation C9-series model. But perhaps you should. Slippery bodywork has always been a calling card of this model line. The very first C4-series version of 1994 was a re-badged version of the most slippery big car of the '80s and '90s, the Audi 100. And the first bespoke design with an A6 badge, the C5-series model of 1997, set another new standard for how slippery a big estate could be. It's successors, the C6 design of 2004, the C7 model of 2011 and this current car's predecessor, the C8 design of 2018, continued the trend of form over function. Customers could fit much more in a rival Mercedes E-Class Estate, but the A6 Avant always vastly out-sold that model in our market, whilst also trumping the other big segment player, BMW's 5 Series Touring. This C9-generation model, announced in early 2025, was originally supposed to switch to 'A7' badging so as not to cause confusion with the all-electric A6 Avant e-tron launched in 2024. But a last-minute change of policy by Audi saw this combustion model keep the 'A6' moniker. It's still offered in diesel form as well as in petrol guise - it'll actually be one of the last diesel models Audi will ever launch. And there's a saloon version too. But here our focus is on the Avant.

Engines and Tech Spec

In a market where rivals are starting to wonder whether they should have been quite so hasty in dropping diesel power, this A6 Avant celebrates the black pump, reserving arguably its most sophisticated engine tech for the TDI version, which uses the company's usual four cylinder 2.0-litre unit. As with the A5 Avant, this means installation of the brand's MHEV plus system, which offers a big step forward from Ingolstadt's previous mild hybrid technology. For one thing, it uses a much bigger e-motor, providing 24PS and 230Nm of torque. For another, it acts as more than just a starter generator, also able to drive the car on its own at parking speeds. Plus, using a brake-by-wire set-up, the system can also regenerate energy at up to 25kW, so the compact lithium battery will always be topped up. As we said, the 2.0 TDI unit in question is a familiar one - and the quattro 4WD system it must be paired with is familiar too. Total output is 204PS, which is the same as the alternative four cylinder engine on offer, the 2.0 TFSI petrol. This can only be front-driven and makes 62mph in 8.3s en route to 144mph, respectively 1.3s and 5mph slower than the diesel. The UK won't get the 3.0 V6 TFSI petrol unit offered on the continent. But we will in future see a range of Plug-in Hybrid TFSI e powertrains, including those likely to be used in the future high performance S6 and RS 6 models. Audi claims drive dynamics have been improved with this C9-generation design. To that end, there's a stiffer torsion bar, stiffer control arm bushings, a more rigid steering rack and increased front camber. All of this is supposed to improve steering feel and road feedback. Plus the sleeker bodywork should help refinement.

Design and Build

This is by far the most dynamic-looking A6 Avant there's ever been. With its lower roof line and pumped-up wheel arches, even an entry-level variant appears to have an S6-vibe. Aerodynamics have been prioritised over practicality, resulting in a low drag coefficient of just 0.25Cd. So it's just as well that the 4,990mm body length is a full 60mm longer than the previous C8-series model. The front end borrows cues from the A6 e-tron and the e-tron GT, with the familiar Audi rings moved from the enormous grille up to the bonnet and the headlights placed higher and wider across the new nose. The sculpted rear has a striking light bar that sits below bright brake lights with OLED panels. Wheel sizes are between 18 and 21-inches. Inside, Audi serves up most premium-feeling cabin in the segment, its architecture similar to recent models like the A6 e-tron, the Q6 e-tron and the Q5 (all developed at much the same time). Which means a huge central fascia panel called the 'digital stage' that houses an 11-inch instrument screen and a 14.5-inch central infotainment monitor in a single curved housing. There's no lower centre stack screen as in the old model, but customers can specify an optional 10.9-inch passenger side display. As long as you don't mind shiny black trimming, you should feel it to be all quite high-end, with high quality soft-touch finishes and leather-like materials wherever you look. There are some nice tech touches, like the optional 'dynamic' sunroof which can be switched between translucent and clear - and also has an interim slatted 'pergola' mode. We're pleased to see the retention of some proper physical controls around the dashboard too. Rear seat space is impressive; even a lanky passenger stuck behind a tall driver will have plenty of leg room. And the swept-back roof line doesn't seem to compromise head space too much. It has though, affected boot space, which once the kick-operated tailgate rises is revealed as 503-litres (down from 565-litres in the old car). That figure rises to 1,534-litres with the rear seats down. These are the smallest-capacity figures in the class, but Audi thinks they'll be quite sufficient for the target market. Thanks to its width of 1,050mm, this is at least a practical space - two large suitcases can fit in side by side. The standard 40:20:40 folding rear seats enable variable loading for items such as ski equipment. A rail system and a partition net come included. 

Market and Model

Let's get to the pricing, pitched from launch from £52,510. There are the usual 'Sport', 'S line' and 'Edition 1' trim levels. Opt for mid-range 'S line' trim (as most customers will) and you'll be offered the change to find an extra £2,650 to get Audi's optional 'Sound and Vision Pack'. This includes a head-up display, headrest speakers, increased charging capacity for the USB ports and a Bang & Olufsen premium sound system with 3D sound. The pack also includes Audi's 'ambient lighting package pro' set-up, which means you get the useful 'dynamic interaction light' which arches around the top of the dash and illuminates in different colours to warn you of safety issues, drive mode selections or 'phone settings. Many customers will also want to pay extra for the optional 'dynamic' panoramic sunroof. Matrix LED headlights come as standard - with a choice of seven digital light signatures for the daytime running lights at the front. Alloy wheel rim sizes range from 18 to 21 inches across the range. The central screen has the latest version of the "Hey Audi" voice-activated Audi assistant, which puts you on speaking terms with numerous vehicle and infotainment functions, from adjusting heating to weather information. And you can control a lot of these features remotely via the my Audi app. 'S line' models get sport exterior touches. And a few well-chosen sporty cabin embellishments, including branded contoured front sports seats. All the usual camera driver assistance safety systems you'd expect are of course included.

Cost of Ownership

Expect around 45mpg on the combined cycle and around 140g/.km of CO2 from the TDI diesel; obviously, you'll do a little worse than that with the 2.0 TFSI petrol version. The key engineering efficiency development with this new A6 Avant is, as we told you in our 'Driving' section, the new 'MHEV plus' mild hybrid system that features on the diesel versions. This is based on a 48-volt on-board electrical system that supports the combustion engine and reduces CO2 emissions while increasing performance. Its added powertrain generator (the 'PTG') enables electric driving components that contribute to a reduction in fuel consumption. The 'MHEV plus' system offers advantages in CO2 emissions compared to the previous MHEV set-up. Over the WLTP driving cycle, these total up to 10g/km of CO2 in the 2.0 TDI. The PTG can also add up to 24PS of electric power to the output of the combustion engine. When decelerating, the PTG feeds energy back into the battery at up to 25kW. As a result, purely electric manoeuvring and parking are possible to a limited extent. Thanks to the option of using an electric air conditioning compressor, the air conditioning system can also be operated when the vehicle is stopped at traffic lights and the combustion engine is switched off. With the integrated and blending-capable brake control system, the brake pedal and the brake hydraulics can be completely decoupled. In models with the 'MHEV plus' system, it achieves the necessary deceleration without using the friction brakes thanks to regenerative braking. This means that deceleration is initially achieved solely by recuperation. The friction brakes only kick in when the brake pedal is pressed harder. The brake feel remains unaffected by this.

Summary

This, even BMW and Mercedes would reluctantly have to admit, is a beautiful piece of engineering. It always has been. The A6 Avant was, after all, the first cars in its class to offer things like bonded-in flush glazing, a galvanised bodyshell, V6 TDI power, four wheel drive and advanced twin-clutch automatic gearboxes. And in this improved smart-suited sixth generation C9-series guise, the cleverness continues, an extra dose of visual charisma blended with high technology and premium quality unsurpassed in this sector. This car's drawbacks, such as they are, don't appear to bother many potential buyers. No it's still not the most spacious large executive estate in its class - but these days, it's large enough for that not to matter. Yes, the extras can be expensive, but then that's the case with any premium executive car. And it's true that the handling still isn't especially aimed at driving enthusiasts, though you can go a long way towards sharpening it by ticking the right options boxes. This then, is a very complete product, perhaps a fitting sign-off for the combustion A6 Avant model line, if that's what this C9-era design is. A thorough case, if ever there was one, of vorsprung durch technic.

Body Glass

Rear wiper

Privacy glass

Front intermittent wipers

Electric front/rear windows

Rain and light sensors

Adaptive windscreen wipers with integrated washer jets

Heat insulating darkened glass in side and rear windows

Heat insulating glass in windshield

Brakes

Electromechanical parking brake

EBD - Electronic brakeforce distribution

Electronic Stability Control (ESC) including ABS, ASR and EDL

19" Disc brakes in front and brake calipers painted in black with "S" lettering (ECE)

Carpets/Rugs

Front and rear floor mats

Chassis/Suspension

Adaptive air suspension

Communication

Voice control system

Bluetooth interface

Audi connect safety and service (e-call)

Audi smartphone interface includes wireless Apple carplay/Android Auto

Audi connect with Amazon Alexa Integration

Driver Aids

Lane departure warning system

Audi drive select

Camera based traffic sign recognition

Dynamic all wheel steering

360 degree camera

Park Assist with parking system Plus

Driver Convenience

Power door closure

Automatic start/stop system with coasting functionality

Power operated tailgate

Operating buttons in black gloss

Remote park assist plus

Driver Information

Service interval indicator

Head up Display

MMI navigation plus with 10.1" and 8.6" touch screens

Audi virtual cockpit

Driving Mirrors

Carbon mirror housings

Frameless auto dimming interior rear view mirror

Electrically adjustable heated and folding + automatically dimming exterior mirrors with memory function

Embellishment Trims

Carbon twill inlays

Engine

Diesel particulate filter

73 litre fuel tank

22 litre AdBlue tank

Entertainment

DAB Digital radio

USB connection

Auxiliary input socket

Bang & Olufsen 3D Premium Sound System

Audi front music interface

2 USB-C ports with charging functionality in the rear

Exterior Body Features

Black roof rails

Panoramic opening glass sunroof

Body colour rear roof spoiler

S front and rear bumpers

S Line side skirts

Matt black side air intake grille with inlay in matt aluminium

Body colour S specific rear diffuser

Rear side wing doors

Radiator grille in anthracite black matt, single frame in chrome and horizontal struts in matt aluminium silver

S air inlet in titanium anthracite black

Exterior Lights

HD Matrix LED headlights with dynamic front and rear indicators

LED third brake light

LED signature front daytime running light

LED rear lights with dynamic indicators

Audi beam projecting the word Vorsprung onto the floor from the driver and front passenger doors

Heating/Cooling/Ventilation

4 zone climate control

Interior Features

Electric rear window blind

Front centre armrest

Height/reach adjust steering wheel

Leather gear knob

Black cloth headlining

Stainless steel pedals and foot rest

Illuminated door sill trims with S logo

Tool kit and car jack

Leatherette on upper instrument panel and door shoulders

Luggage compartment system

Valcona Leather with contrast stitching and S embossing + front super sport Seats + dinamica door insert

Electric steering column

3 spoke sport leather steering wheel with multifunction, shift paddles and steering wheel heating

Front sliding sun visors

Interior Lights

Audi phone box light

Packs

Storage pack - A6

Non smoking pack - A6

Full leather pack - A6

City assist pack with front cross traffic assist - A6

Multi coloured extended LED interior lighting pack - A6

S line exterior style pack - A6

Ambient lighting package plus - A6

Tour pack with adaptive cruise assist - A6

Safety

3 point seatbelts on all seats

Warning triangle and first aid kit

Extended pedestrian protection measures

Seatbelt monitoring

Audi pre-sense front

Tyre pressure warning light

Airbags - Front side, front and rear including head

High tyre pressure measurement system (TPMS)

Manual child proof rear door locks

ISOFIX child seat mounting for front passenger seat and ISOFIX child seat mounting with Top Tether for outer rear seats

Seats

Heated front and rear seats

Rear headrests

Front head restraints

Electrically adjustable front seats with memory including seat height, fore/aft position, backrest angle and 4 way lumbar

40/20/40 split folding 3 rear seat bench in 3 parts with rear centre armrest

Single front passenger seat

Security

Immobiliser

Remote central locking

Advanced key

Keyless Go

Anti theft alarm with tow away protection

Anti-theft wheel bolts and wheel loosening detection

Transmission

Quattro with sport differential

Vanity Mirrors

Illuminated sun visors with vanity mirrors

Wheels - Alloy

21" 5 twin spoke matt dark grey audi sport alloy wheels in gloss turned finish

Emissions - ICE

HC: N

Standard Euro Emissions: EURO 6

WLTP - CO2 (g/km) - Comb - TEL: 192

WLTP - CO2 (g/km) - Comb - TEH: 194

WLTP - CO2 (g/km) - Comb: 192

Engine and Drive Train

Catalytic Convertor: No

Engine Code: 4A5SPA

Gears: 8 SPEED

Transmission: SEMI-AUTO

Engine Layout: NORTH SOUTH

Cylinders: 6

Cylinder Layout: V6

Number of Valves: 24

Camshaft: DOHC

Fuel Delivery: COMMON RAIL

CC: 2967

Fuel Consumption - ICE

WLTP - MPG - Comb: 38.7

WLTP - MPG - Comb - TEL: 38.7

WLTP - MPG - Comb - TEH: 38.2

WLTP - FC (l/100km) - Comb: 7.3

WLTP - FC (l/100km) - Comb - TEL: 7.3

WLTP - FC (l/100km) - Comb - TEH: 7.4

General

Did at least one aspect of this vehicle's safety give cause for concern?: 0

NCAP Adult Occupant Protection %: N

Special Edition: 0

Special Order: 0

Based On ID: N

Insurance Group 1 - 50 Effective January 07: 49E

Service Interval Mileage: 18000

Service Interval Frequency - Months: 24

Alternative Fuel Qualifying: 0

NCAP Child Occupant Protection %: N

NCAP Pedestrian Protection %: N

NCAP Safety Assist %: N

NCAP Overall Rating - Effective February 09: N

Badge Power: 344

Badge Engine CC: 3.0

Vehicle Homologation Class: M1

AdBlue: No

Generation Mark: 6

Coin Description: TDI Quattro

Manufacturers Corrosion Perforation Guarantee - Years: 12

Manufacturers Paintwork Guarantee - Years: 3

Standard manufacturers warranty - Mileage: 60000

Standard manufacturers warranty - Years: 3

Coin Series: Vorsprung

Performance

Engine Torque - MKG: 71.4

Engine Torque - NM: 700

Engine Torque - LBS.FT: 516

Engine Power - KW: 253

Engine Power - BHP: 344

Engine Power - PS: No

0 to 60 mph (secs): 0

Engine Torque - RPM: 1750

Top Speed: 155

0 to 62 mph (secs): 5.1

Test Cycles

Emissions Test Cycle: WLTP

RDE Certification Level: RDE 2

Tyres

Tyre Size Spare: TYRE REPAIR KIT

Tyre Size Front: 255/35 R21

Wheel Type: 21" ALLOY

Tyre Size Rear: 255/35 R21

Space Saver?: 0

Alloys?: No

Wheel Style: 5 TWIN SPOKE

Vehicle Dimensions

Length: 4954

Width (including mirrors): 2110

Height: N

Width: N

Height (including roof rails): 1481

Wheelbase: 2928

Weight and Capacities

Minimum Kerbweight: 2020

Max. Towing Weight - Braked: 2000

Turning Circle - Kerb to Kerb: 12.1

Gross Vehicle Weight: 2655

No. of Seats: 5

Luggage Capacity (Seats Up): 550

Fuel Tank Capacity (Litres): 73

Max. Loading Weight: 635

Max. Towing Weight - Unbraked: 750

Exterior Body Features

Pearlescent paint

Audi exclusive metallic paint

Metallic paint

Paint - Metallic

Metallic - Chronos grey

Metallic - Firmament blue

Metallic - Ascari blue

Metallic - Mythos black

Metallic - Floret silver

Metallic - Glacier white

Metallic - Grenadine red

Paint - Pearlescent

Pearl - Daytona grey

Paint - Solid

Solid - Brilliant black

Paint - Special

Audi Exclusive Metallic - Custom

Service/Warranty

Audi warranty - 4 years or 75000 miles

Audi warranty - 5 years or 90000 miles

Towing

Electrically swivelling trailer towing hitch

Trim - Leather

Valcona leather - Rotor grey with anthracite contrast stitching + front super sport seats with S embossed logo + dinamica door insert

Valcona leather - Black with rock grey contrast stitching + front super sport seats with S embossed logo + dinamica door insert

Wheels - Spare

Space saver spare wheel and jack