Audi A8 4.2 TDI 2006 Review

What we liked
» Performance and righteous fuel consumption
» Excellent dynamics with AWD surety
» Competitively priced in this mega-dollar class

Not so much
» MMI -- better than others (just)
» Pragmatic styling lacks rivetting presence
» Seductive luxury, but we had to return it (sob)

Anyone who thought diesels' invasion is concentrated exclusively upon SUVs, small to mid-size cars and upmarket medium models, must now think again.

Audi's $210,000 A8 4.2 TDI extends the diesel challenge to the uppermost luxury class, and in doing so means Audi is oiling the offensive at every level its models occupy (including A3, A4 and A6, not to forget the Allroad and upcoming Q7).

Launched recently in Australia to complement Audi's wider sales strategy, the A8 saloon's latest 4.2-litre V8 diesel embodies the company's advanced TDI technology. That's the very same technology that helped its special V12 diesel powered R10 sports-racer win epic success (first and third) in the 2006 Le Mans 24-Hour Race.

For A8, the V8's specification includes two variable-vane turbochargers, intercoolers, swirl flaps within the induction system and extra high pressure (1600 bar/23,500psi) direct injection. These features contribute to the 4.2 TDI's very healthy 240kW maximum power and stupendous 650Nm maximum torque.

Claimed to leap from 0-100km/h in under six seconds, the 4.2 TDI therefore performs in the same league as BMW's slightly costlier 4.8-litre V8 750i, and is considerably quicker than Mercedes-Benz $204K V6 350L S-Class, though a bit behind the $254K 5.5-litre V8 S-Class.

The Audi's acceleration also beats the $171K Lexus LS 4.3-litre V8, and shades other A8 petrol V8s.

Besides being one of the quickest movers in its price range, the A8 4.2 TDI completely out-shines rivals in fuel consumption for its official usage is 9.7lt/100km, whereas comparable luxury models chew through mid to high 11s. The TDI's cruising range between refills far exceeds its rivals'.

Clearly, this car presents a persuasively strong case on paper. No less on the road either. The A8 4.2 TDI is not only a great way to travel, but equally (even perhaps surprisingly) it is a remarkably good thing to drive.

The performance constantly impresses with the combination of massive vigour and syrupy smooth refinement. Importantly, the TDI manages to sound seriously powerful (which it is), but never loud or crass.

From outside it's hard to pick as a diesel, and from inside you'd never know.

The remainder plays A8's role as skilfully and luxuriously as expected. For such a large, hefty car, the 4.2 TDI steers relatively keenly, brakes arrestingly, handles quite deftly even when pushed, and the properly disciplined air-spring suspension is comfortably bump-absorbent across whatever the road may throw at it.

The V8 TDI's quattro AWD system is a constant ally in putting the power to ground very effectively, though without corrupting the sense of fore-aft balance and responsive attitude, as some do.

Besides all of which, the welcoming cabin's perceptibly plush and very hospitable accommodations are another truly rich experience.

In sum, then, for luxury-car shoppers the A8 4.2 TDI commands earnest attention because it is a fine car regardless, and a bit different (even arguably a degree superior), in partnership with this remarkable V8 diesel.

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