Audi A6 Allroad Diesel 2015 Review

When you're facing an uphill battle to regain segment supremacy, opt for diesel. That's Audi's approach to its facelifted A6 large prestige vehicles.

Its base model 1.8-litre four-cylinder turbo is the only petrol-powered vehicle now in the regular range.

The revised diesel engines are notable for their refinement and reduced fuel consumption - the best-selling 2.0-litre turbo diesel four cylinder now uses just 4.2L/100km, based on the European test cycle.

Audi has also ditched the continuously variable 'Multitronic' transmission in favour of a seven-speed dual-clutch auto that adds to the sportiness and cuts fuel consumption.

The regular A6 Avant (wagon) will be dropped from the new line-up, though the higher-riding and tougher-looking Allroad will be retained, along with the astonishingly quick bi-turbo V8 RS6 Avant.

The update comes as sales of the current A6 have surged by more than 28 per cent year to date.

The first cars are expected to arrive in Australia in March-April, heralding another step in Audi's push to overtake BMW as the No. 2 prestige importer by 2016.

VALUE

Audi says there will be far more features with only a minor adjustment to prices, which currently start at $77,900 for the front-drive 2.0-litre petrol model. The update will have a smaller displacement engine, a turbo 1.8-litre, but outputs are up and fuel use is well down.

The same applies to the 2.0-litre turbo diesel, which currently costs $79,500. Both entry cars are front-wheel drive - buyers have to step up to the six-cylinder diesels to add the all-paw quattro drivetrain.

The regular quattro model is the only version to lose power. The 3.0-litre turbo diesel comes in 160kW specification, which should bring the price below the existing model's $108,400.

Topping out the A6 range is a twin-turbo variant cranking out 235kW and 650Nm. That engine is matched to an eight-speed conventional automatic transmission - the seven-speed dual-clutch struggles to cope with so much torque.

Prices shouldn't shift far from $119,700.

TECHNOLOGY

The information display has been updated, though it still lacks the app-based connectivity available in the US and Europe. Drop a data SIM into the car and the A6 will now harness the mobile 4G network to speed up in-car connectivity.

The driver's display now has a secondary hi-res satnav screen nestled between speedo and tacho.

It's a marked improvement without being as clever as the Audi TT's virtual cockpit.

Audi spokesman Shaun Cleary says that adopting the TT's technology would have required a new wiring loom and that was ruled out for the facelift.

DESIGN

Eagle-eyed car fans will note the minor tweaks to the front bumper and the slimmer LED tail-lights but the average observer won't appreciate it's an updated model, given most of the changes are to the drivetrain and interior electronics. The changes add 17mm to the A6's length.

SAFETY

The A6 is a five-star vehicle. ANCAP scored it 34.91/37 when it launched in 2011.

The result would have been even more impressive had the driver's door not unlatched in the side impact crash test, a flaw that cost the car a full point.

DRIVING

Most Australian buyers don't tick the option for airbag suspension and that's a good thing. Outside of chauffeur duties - in which case the A8 is the machine of choice - the suspension trades off too much feel for what the car is doing, even if it does pamper passengers.

The more conventional steel springs weren't available to test, so CarsGuide tested the glass fibre reinforced plastic springs used in the new wagon models, after being assured they'd been developed to mirror the performance of the existing metal coils.

If that's the case, there is a minor trade-off in terms of compliance over small ridges and ruts. The upside is far more feel for what the car is doing. Money well saved, then.

The 2.0-litre diesel is more than capable of hauling the A6 around and there is no aural indication in the cabin that it's an oil-burner.

Put that down to improved noise insulation, topped by acoustic windows. The expected price trim for the entry level quattro six-cylinder should make it the pick of the bunch. The 500Nm make short work of stop-start city traffic and give the A6 far more punch on the highways than state governments are comfortable with.

The switchgear looks dated in contrast to Audi's latest 'all-new' TT model, though the build quality and adjustment feel can't be questioned.