Skip advert
Advertisement

Audi A6 3.0 BiTDI

Powerful diesel makes saloon even stronger

The Audi A6 and BMW 5 Series have been locked in battle for years. The latest generations of both have held Auto Express Best Executive Car titles and are the benchmark the new Lexus must face up to.

Worryingly for the GS 450h, though, the latest addition to Audi’s armoury is a potent diesel engine which is designed to offer class-leading performance. The new BiTDI is the most powerful V6 TDI yet, pumping out 309bhp and a whopping 650Nm of torque. We’ve tested the car in S line trim, and its sporty styling cues subtly enhance the A6’s slightly uniform and bland looks.

Advertisement - Article continues below

Still, if the exterior leaves you cold, the interior is sure to win you over. Beautifully clear yet upmarket instruments blend with Audi’s intuitive MMI control system and a perfect driving position to create a very functional and comfortable cabin.

The quality is faultless, while classy trim and swish design ensure it’s luxurious without being ostentatious. Standard kit is generous and the navigation screen gracefully slides out from the dash.

However, the real star of the show comes to life when you press the centre console-mounted start button. The 3.0-litre TDI engine hums gently at idle and is really smooth throughout the rev range, while the effortlessly rapid performance is nothing short of sensational. Quattro all-wheel-drive traction helps the A6 cover 0-60mph in only 5.6 seconds – but it’s real-world muscle that counts here, and the Audi doesn’t disappoint.

Skip advert
Advertisement
Skip advert
Advertisement - Article continues below

Used - available now

A6

2021 Audi

A6

24,094 milesAutomaticPetrol2.0L

Cash £19,912
View A6
A6

2021 Audi

A6

33,313 milesAutomaticDiesel2.0L

Cash £20,500
View A6
A6

2021 Audi

A6

34,002 milesAutomaticPetrol2.0L

Cash £22,300
View A6
A6

2021 Audi

A6

28,294 milesAutomaticPetrol2.0L

Cash £27,500
View A6

The eight-speed Tiptronic gearbox takes a while to react when you press the throttle at low speeds, yet with all that torque the engine doesn’t take long to get into its stride. And while the 535d is fractionally quicker in-gear, nobody will feel short-changed by the BiTDI’s performance, especially as the engine sounds so good. It’s as refined as you’d expect, but Audi has fitted a clever sound actuator in the tailpipe that artificially creates a sporty petrol-like exhaust note. Clever stuff.

The good news continues in corners, where the tightly controlled body roll and huge grip really impress and help this big saloon to feel smaller and more agile than its rivals. Also, Audi’s Drive Select system allows for fine-tuning of the chassis, although the differences between modes are subtle.

With a 20mm lower ride height and optional 20-inch wheels, our S line test car didn’t ride as well as the BMW, but the accurate steering, composed handling and scintillating performance ensure this is a diesel saloon to enjoy on a back road.

Unfortunately, despite stop-start the A6 has the highest emissions in the test – something that could deter company car drivers looking to minimise their tax bills. Could that be enough to cost this very desirable Audi victory in such a closely fought battle?

Details

Chart position: 2Why? We are big fans of the latest A6, and the new bi-turbo 3.0-litre TDI engine gives it even more punch and desirability. We test the car in sporty S line trim.

Skip advert
Advertisement

New & used car deals

Audi A6

Audi A6

RRP £39,640Avg. savings £7,364 off RRP*Used from £16,483
BMW 5 Series

BMW 5 Series

RRP £52,195Avg. savings £6,739 off RRP*Used from £31,995
Audi A4

Audi A4

RRP £34,385Used from £14,824
BMW 3 Series

BMW 3 Series

RRP £33,315Avg. savings £4,070 off RRP*Used from £11,990
* Average savings are calculated daily based on the best dealer prices on Auto Express vs manufacturer RRP
Skip advert
Advertisement

Most Popular

New Kia PV5 Passenger MPV undercuts the VW ID.Buzz by a huge £25k
Kia PV5 Passenger - show front

New Kia PV5 Passenger MPV undercuts the VW ID.Buzz by a huge £25k

New entry into the electric people carrier market undercuts the VW ID. Buzz by a significant margin
News
29 Apr 2025
Car Deal of the Day: BMW’s ultimate luxury SUV at an unusually low price
BMW X7 - front

Car Deal of the Day: BMW’s ultimate luxury SUV at an unusually low price

German firm’s flagship SUV could never be called cheap but it is exceptional value at £735 a month – making it our Deal of the Day for Sunday 27 April
News
27 Apr 2025
New 2025 Kia PV5 van starts from a tempting £22,645
Kia PV5 Cargo on display at Commercial Vehicle Show - front 3/4

New 2025 Kia PV5 van starts from a tempting £22,645

All-new entry into the van market promises competitive pricing and comes with a range of up to 247 miles
News
30 Apr 2025