2006 Audi A8 Reviews

Midway through 2006, Audi added the option of a turbo-diesel to its topline A8 series.

Another day, another diesel. The CARSguide team has tested so many oil-burners in the past few months that you would think diesel was the dominant fuel in Australia.Well, it isn't and car companies still face a big battle to convince Australians that paying a premium to buy a diesel is worth it.The image of diesel has moved forward from the days it was associated with smoking four-wheel-drives, but it still has a way to go.Hoping to help change the image, several premium brands are importing diesel engines for some of their most expensive models, including 4WDs and sedans.Audi is even importing a diesel version of its range-topping A8. This is the model that takes on the cream of the German limos, including the Mercedes-Benz S-Class and the BMW 7-Series.The A8 range starts with a 3.7-litre petrol V6 for $169,950, then jumps to $204,500 for the 4.2-litre petrol V8.So where does the diesel A8 sit in the range? Right on top of the regular models at $210,000.Only the stretched A8s are more expensive. That is a lot of cash to cough up for any car.But this diesel is different. It's not designed with fuel savings in mind. After all, the type of high-rollers who might buy this are about as interested in fuel prices as they are about price rises for a slab of VB.The diesel donk in the A8 is about sheer force. It has 4.2-litres and eight cylinders assisted by two big turbos that spool-up to produce a healthy 240kW at 3750 revs — quite incredible for a diesel.What is more impressive is the torque total — a whopping 650Nm.To put that into context, the new 6.0-litre V8 in the Holden SS Commodore produces 530Nm and the Ford Falcon XR6 Turbo churns out 480Nm. This poke allows the big A8 limo, which weighs 1945kg, to dash from 0-100km/h in 5.9 seconds.All the urge runs through a six-speed automatic and is fed to all four wheels.Though the Audi boffins designed the engine with performance in mind, the fuel economy is also good. The official figure is 9.7 litres for 100km of city and highway driving.This means owners could drive for 950km without having to stop for fuel.Just as you would expect for a car that costs six-times the price of a base Commodore, the A8 TDI comes fully loaded.It has all the safety gear with all the electronic assistance and a full-suite of airbags, as well as luxuries including a 17cm colour centre information screen with satellite navigation and TV tuner, eight-speaker premium sound system, leather seats, sunroof, xenon headlights that swivel to point around corners and a keyless start.Another feature to delight the tech-heads is a fingerprint ID system that allows the car to recognise the driver and adapt accordingly.ON THE ROADTHE engine in the A8 is the best diesel we have driven. The burst of torque from the bottom of the rev range is simply brilliant.It slings the A8 forward with such force that you look forward to the next stop, so you can go through the acceleration process again.With the tricky variable geometry turbos working hard to smooth out the power delivery, the diesel surge runs all the way to the red-line.The turbos pause only slightly before turning on the punch, a long way from the turbo lag that some smaller diesel engines still have.Fuel consumption is not fantastic compared with many smaller diesels, but is excellent when you consider how potent the engine is.The fuel economy figure we achieved on the test ran from about 8.5 litres/100km on the highway to 11 litres when pushed.The automatic transmission is well suited to the punchy diesel and you hardly notice it.You can, of course, use the paddles on the steering wheel, which shout "gimmick". The paddles are next-to-useless because the gearbox over-rides the driver and changes up anyway, even when the automatic is flicked into manual mode.And with 650Nm of torque on tap, it is not as though you are going to have to work the gears to extract enough punch from the engine.The A8 has exceptionally light steering, which is nice when you are cruising around town or trying to park in tight spaces. The downside is that it is too light if you ever feel like getting sporty on a twisty road, and there is virtually no feedback through the wheel for the driver.The big German's adaptive air-suspension works quite well. It depends on your taste, but we found the standard suspension setting a touch too firm and the Luxury setting was too soft over any types of bumps.The system absorbs most bumps with ease but, strangely, some small things such as cats-eye reflectors seem to send a jolt through the aluminium body.When it comes to creature comforts, the A8 excels. Lots of things help out in everyday driving but many are there just to be shown off to friends.The centre control screen is super-crisp, thanks to high-resolution colour graphics, and the MMI (Multi Media Interface) is the best control system in a luxury German car.Seat comfort is excellent and there is a mass of interior space, including in the huge boot. The only thing missing from the cockpit is heated seats. They are optional, but should comes standard on such an expensive car.THE BOTTOM LINEThe storming diesel engine is simply stunning and makes diesel make sense, and we'd pick it over the V8 petrol.SCORE: 80/100FAST FACTThis is the first time Australian customers can order an A8 with a diesel.SPECS$210,000 as testedENGINE: 4.2-litre V8 turbo-diesel with two VTG turbochargersPOWER: 240kW at 3750 revsTORQUE: 650Nm at 1600-3500 revsTRANSMISSION: Six-speed automatic with sports shift, all-wheel-driveBODY: Four-door sedanSEATS: FiveDIMENSIONS: length 5062mm, width 1894mm, height 1444mm, wheelbase 2944mm, tracks 1629/1615mm front/rearSTEERING: Speed-dependent rack and pinionFUEL TANK: 90 litresFUEL TYPE: DieselFUEL CONSUMPTION: 9.7 litres/100kmWEIGHT: 1945kgSPARE TYRE: Full-size spareBRAKES: Discs all roundTYRES: 255/40R19SAFETY GEAR: Anti-skid brakes, electronic stability control, eight airbagsWARRANTY: Three-years/unlimited kmSTANDARD FEATURESAirconditioningCruise controlAlloy wheelsClimate controlLeather seatsParking sensorsAutomatic wipersHOW IT COMPARESMercedes Benz S500: 79/100 (from $253,900)BMW 750i: 73/100 (from $213,500)Audi A8 4.2 (petrol): 78/100 (from $203,000)

What do you do when it's mere moments from the only hour of TV that you really need to watch every week and the power goes out?If an Audi A8 4.2-litre V8 TDI just happens to be parked in your driveway, you simply leave the sitting room and turn the massive diesel's power on.Not only is this A8 blessed with an earth-moving, twin-turbo monster under the bonnet, it also has a TV tuner.Crisis solved.If it looked a little odd — bathed in the glow of Top Gear while seated in a darkened street — it was certainly comfortable with the heater on.The only downer was being unable to toast my marshmallows, as seat heating is an option in a car that comes in at more than the double tonne in price and weight.Moving along, the A8's fun factor increases exponentially.The 246kW and 650Nm produced by its 4.2 V8 could put a smile on anyone's dial — and if our locally based manufacturers would explore diesels, maybe our government fleets could be run with less pain to the taxpayer.Having kicked around town for two days, it was off down the freeway just to see how the A8's quattro grip held on.On the open road at 110km/h, the big diesel barely gets above idling speed; this car could cruise at double that velocity and still have abundant overtaking power up its sleeve.Many times, while going around slower vehicles, the reins had to be well and truly tugged to get it back on the right side of the lane markers.Once the A8 has a sniff of an open throttle, holding it back is as much a job as keeping it at normal speeds.The latter task is best left to Audi's version of radar cruise control. Once set, it will keep the car travelling at your desired speed until other traffic is encountered and overtaken safely.I found it better than the version tried recently in BMW's 550i — designated 10km/h increments work better than guessing via gauges.Ride quality is, of course, excellent, with adaptive air-cushioned suspension constantly monitoring road conditions and driver inputs to deliver the optimum combination.It's so good that a few times I was caught out on corners that sharpened mid-apex — it could also have been due to the long drive after the working week and a slightly docile driver at the wheel.Audi cabin comfort gets top marks, as always.The front seats have more power than certain cheap cars, and with the vast amount of space in the rear you'd have to be running a multi-national media empire to need the even bigger A8L version.The power-operated boot (opening and closing) has enough room for your Sunday-morning golf clubs and luggage for the drive to your country house.Most impressive is that, even carrying this sort of weight, the V8 diesel ate up the kilometres effortlessly and achieved an amazing 900km from one tank of the smelly stuff.It was filled up above the reserve fuel level only to hose down my lovely wife's paranoia at the prospect of having to hitch a ride near the Belanglo State Forest.At least we could have watched telly while we waited.Almost worth $210,000, when you think about it ...

Boasting the sporty three-litre V6 TDi engine, which powered the A6 to a "Best Luxury Car over $57,000" gong in Australia's Best Car awards last year, the A4, priced at $86,700, delivers as "the most-powerful six-cylinder TDi in the B-segment".The C220CDi Mercedes-Benz diesel offers 110kW and 430Nm, while the newly introduced BMW 320d produces 115kW and 330Nm, although both are four-cylinder offerings.The new Audi V6 powerplant is a common-rail direct injection unit that uses piezo injectors (voltage-activated injectors that are very quick and precise) and runs 1600bar of pressure in the fuel delivery system.Multiple fuel injections per cycle and two intercoolers for the single turbocharger are among the other engine bay highlights.With 171kW of power and 450Nm of torque on tap, six-speed tiptronic transmission and speed-sensitive power steering, the A4 seamlessly (and frugally) cruises but has the capacity to reach 100km/h in 7.5 seconds.Similarly, the $210,000 supercar A8, with its all-new 4.2-litre, eight-cylinder twin-turbo engine, lightweight Audi space frame and quattro all-wheel drive, also turns it on.The turbodiesel V8 comes from the same family as the new V6 in the A4, using the same high-pressure common-rail direct-injection principles, and boasts a weight of 255kg, down by 15kg over its smaller predecessor.Like the A4, the engine is of low-weight, compact design, with Audi claiming a new benchmark in acoustics.The V8 has two turbochargers, with variable turbine geometry, assisting in reducing lag and generating higher torque at lower engine speeds, as well as two intercoolers.With 240kW and 650Nm the high-performance limousine accelerates from 0 to 100 in just 5.9sec.The new powerplant is so quiet it's easy to forget you are driving a diesel.The A8's 4.2 TDi engine's twin-pipe exhaust system is also equipped with a diesel particulate filter — made to last the lifetime of the vehicle without additives or servicing — which further decreases the engine's emissions, which in greenhouse terms are already low.And while Australian motorists do not have the privilege of discounted diesel prices, rebated registrations and the reduced taxation offered to their European counterparts, the models' fuel economy is incentive enough.Averaging 8.4 litres per 100km under Australian Standards testing, the A4 offers around 750km per tank; with just 9.7 litres per 100km fuel consumption, the A8 pushes close to 1000km.Both models feature electric front seats complete with electric lumbar support and leather upholstery.Positioned behind the sports leather steering wheels, driving from Hobart to Launceston was a pleasure.Travelling vast highways, curly mountain roads and even navigating unsealed stretches in winter conditions with ease, both the A4 and A8 lived up to the expectation that the sporty-yet-safe luxury models would be smooth operators.