Car Reviews: 2005 Audi A8

For the past decade, Audi has invested heavily in technology intended to establish itself once-and-for-all on equal terms with German heavyweights BMW and Mercedes-Benz. The company's flagship sedan, the 2005 Audi A8, suggests Audi has not only matched its primary rivals in most areas, but surpassed them in some.

The A8 is Audi's largest, most sophisticated sedan: Comfortable, fast and very smooth. Yet those qualities are the baseline for full-size cars in this price range. The A8 is the newest of Germany's Big Three luxury sedans, and it raises the performance bar in many respects. It's more refined that the Mercedes S-Class, and more handsome to many than BMW's 7 Series. Nor is Audi resting on the A8's achievements. All new for model year 2004, the A8 nonetheless adds features for 2005. The line has been expanded with two new variants, including the ultra-luxurious, 12-cylinder A8 L 6.0.

A8's redesign a year ago was thorough. Its wheelbase was stretched to provide even more room and comfort for rear-seat passengers, which can be crucial in this type of executive-class transport. Its 4.2-liter V8 engine was revised to generate more power, and matched to a six-speed Tiptronic automatic that allows better fuel mileage than the previous five-speed automatic. This drivetrain delivers instant response to the driver's demand for acceleration, while quattro all-wheel drive and an adaptable air suspension provide a seemingly ideal balance between handling and ride quality. Audi's unique Aluminum Space Frame, a lightweight, highly rigid structure that bonds the car into one cohesive unit, augments the supreme sense of control with Gibraltar-like stability. The A8's cabin is elegant and comfortable, and tops the class in finish quality. Audi's Multi-Media Interface, which comprises the company's attempt to integrate controls for various features and electronic systems, is easier to learn than BMW's controversial iDrive.

For 2005, Audi has launched a shorter-wheelbase A8 in the United States. A standard in Europe for years, this A8 delivers all the performance and luxury for buyers who don't need such a cavernous backseat, and makes parallel parking easier. Audi also launches the elite A8 L 6.0, with its unique look, unusual W-configured 12-cylinder engine and a whopping 440 horsepower. It's the only 12-cylinder sedan from Germany's Big Three luxury brands with all-wheel drive. Finally, all A8s get two new features: Soft Touch doors, which pull the side doors shut from a partially latched position, and Automatic Key, which allows the owner to unlock the doors and start the car simply by walking up and sitting down.

Better still, the new standard wheelbase A8 ($66,590) and the A8 L 4.2 ($68,500) are priced below the long-wheelbase BMW 745Li ($72,500) and standard-wheelbase 745i ($68,500), which don't offer all-wheel drive. The A8 also has a significant price edge on the rear-drive Mercedes S430 ($72,600) or S500 ($81,000) and the all-wheel-drive S430 4Matic ($75,500). The advantage holds with the 12-cylinder models as well.

The 2005 Audi A8 is available in three variants: the A8 4.2 quattro ($66,590); the A8 L 4.2 quattro ($68,500); and the A8 L 6.0 quattro.

New to the United States this model year, the A8 4.2 is known within Audi as the "normal wheelbase" car. It has all the power, technology and convenience features of the A8 L 4.2, which was introduced here in June 2003. The difference? The A8 4.2's wheelbase, and overall length, are 5.1 inches shorter than that of the A8 L (L stands for long wheelbase). Inside the car, those 5.1 inches translates entirely into a reduction in rear-seat legroom. Choose the A8 over the A8 L if squeezing into tight parking spots is more important than a vast rear seat, remembering that the standard A8's rear accommodations are still quite expansive by typical sedan standards.

The 2005 A8 4.2 models are powered by a 330-horsepower 4.2-liter four-cam V8 with Audi's five-valve-per-cylinder technology. A six-speed automatic transmission with Tiptronic manual shift control is the only transmission offered, feeding power to Audi's standard quattro fulltime all-wheel-drive system.

The A8 4.2s come loaded with all the luxury features you'd expect at this price point. The air-conditioning system, for example, uses temperature, moisture, and infrared sensors to detect and demist the windows before they can even think about fogging. Similar to that of the BMW 7 Series and Jaguar XJ series, the A8's parking brake is electromechanical, which in other words means a switch. Advanced Key and Soft Close doors are standard features.

Options include massage, heating and ventilation features for the front seats, four-zone automatic climate control with individual rear-seat settings and a wood steering wheel. A solar-cell sunroof produces enough electrical energy to supply the passenger compartment continuously with fresh air via the blower even when the ignition is off.

The A8 L 6.0 (expected to retail for about $117,500) comes with all of the above and more. New for 2005, the 6.0 features Audi's unique, 440-horsepower W12 engine (literally two Vs), and ultra-luxury amenities. These include power sunshades for the rear windows, heated power-adjustable rear seats, and leather upholstery on the door panels, console and dashboard. The 6.0 also comes standard with a full-length rear-seat center console, housing elaborate climate and seat adjustments, and limiting seating capacity to four.

The A8 L 6.0 offers three options: a 20-inch wheel/performance tire package, upgraded from standard 19-inch wheels and not offered by BMW or Mercedes; radar-managed Adaptive Cruise Control, which maintains a prescribed distance to traffic ahead; and a rear-seat entertainment package with DVD player and two LCD screens in the back of the front headrests. The rear center console can be deleted in favor of a three-place bench seat.

Elegant. That's how we'd describe the A8 in a word, but elegant in a forceful fashion that's not at all prissy. The A8's distinct wedge shape features a short front overhang, a low hood-line and a high, powerful tail. The shoulder line rises to the rear, creating the impression of a crouched beast ready to spring. The A8 is expressive in an understated Audi way and people will know you know business when you fill their mirrors. The front end of the A8 4.2 sports Audi's traditional dual horizontal grilles with flush-fitted headlamps. Projector-beam fog lights sit below the well-integrated front bumper.

Nearly 17 feet in length, the A8 L is longer than the Mercedes S-Class and long-wheelbase BMW 7 Series models. Its wheelbase stretches 121.1 inches (116 inches on the standard A8), essentially identical to its European competitors and substantially longer than that of the Cadillac DeVille. Other things equal, a longer wheelbase offers more passenger room and increased stability at speed. The Audi is slightly wider than the Mercedes and comparable to the BMW. Its rear doors are long, allowing easy access to the rear seat.

All the doors open extra wide, making it easier to get in and out. The flush, lever-style outside handles are attractive, but we find them harder to use than the type you can put your hand through, such as those on a Mercedes.

The A8 4.2s feature seven-spoke 17-inch alloy wheels with 255/55R17 tires; these provide excellent handling and ride comfort and superb grip in the wet. The optional 18- and 19-inch wheels and tires more aggressively fill the wheel wells and provide a surprisingly smooth ride in spite of their short sidewalls. The 12-cylinder A8 L 6.0 gets the 19-inch wheel/tire package standard (20-inch wheels are optional).

The 6.0 features a tall, vertical grille the company calls "the new formal idiom of Audi design." The new grille connects Audi's familiar horizontally split grilles over the front bumper, emphasized with a chrome surround and chrome horizontal slats. It's similar in design to the grille on the all-new 2005 Audi A6. The 4.2 models feature Audi's traditional split grille.

The A8 L is the first car with LED headlights. Its low beams consist of five light-emitting diodes developed jointly with a California-based company. Audi says these lights draw considerably less current than halogen or xenon bulbs to deliver an equal amount of light. Less current draw means that the alternator, which generates a car's electricity, doesn't have to work as hard, and therefore robs less power from the engine. The A8 L 6.0 is the first car with daytime running lights that have virtually no impact on fuel economy, and full low-beam operation requires far less alternator draw than conventional lights.

The rear of the A8 models feature taillights that fit flush with the clean rear design. Turn signals use LED technology and feature side repeater lamps to signal your intentions to drivers alongside. Dual exhaust pokes from below the beautifully integrated rear bumper.

Audi also says the A8's aluminum space frame (ASF) saves about 300 pounds compared to a conventional steel frame, allowing more features without overburdening the car with weight. Still, an A8 L 4.2 weighs more than a BMW 745Li and more than an all-wheel-drive Mercedes S430 4Matic, both of which have more conventional steel-intensive construction. But the ASF offers other advantages. It uses fewer parts with fewer joints for increased rigidity. Increased rigidity means less flex, and the A8 feels as if it's milled from a single block of bar-stock aluminum. That improves just about everything else in the car, from ride quality to handling to overall smoothness.

labor intensive, allowing the doors to open and the A8 to start with a button as long as the coded key fob is within a certain proximity. The Soft Close feature automatically sucks the side doors shut from a partially latched position.

In the 2005 Audi A8, a driver can use the Driver Information Display to set the optional Adaptive Cruise Control, which minds tailgating and maintains a safe, pre-determined distance to the car ahead. The Electronic Stabilization Program can help control the car when the driver can't. Electronic Brake-force Distribution keeps the car balanced in a panic stop, and Brake Assist slams the binders harder if the driver doesn't press as hard he or she should. Adaptive Air Suspension keeps the ride smooth and tires planted no matter the surface. There are moisture-sensing wipers, high-intensity headlamps and ten airbags. Yet all these advanced systems, identified by a confusing array of acronyms, don't mask one crucial point. The A8 can be a complete joy to drive, reminding all but the sensory deprived how pleasant gobbling miles in a big, fast luxury sedan can be.

The first impression at the wheel of an A8 is its smoothness. There's nothing remotely resembling a squeak or rattle, and almost no vibration in the cabin.

The A8 can be a thrill to drive. The 4.2-liter V8 delivers powerful acceleration, but its power delivery is sophisticated, not crude. The engine was revised for 2004, and it delivers more power than its predecessor. Both the short- and long- wheelbase A8 4.2s can sprint from 0 to 60 mph in just 6.3 seconds, according to Audi, impressive given their size and weight. Top speed is electronically governed at 130 mph. The V8 responds with a muted roar to every poke at the gas pedal. No matter how fast the A8 4.2 is already going, the driver can tap into a deep well of acceleration-producing torque.

And if that isn't enough, you can raise the ante with a 6.0-liter 12-cylinder engine. New for 2005, the A8 L 6.0 gets Audi's unusual W12, which is actually two single-cylinder-head VR6 engines, splayed like two Vs and mated at the crankshaft. Each bank has its own computer controls and throttle.

Other things equal, is this W design more powerful or economical that a conventional V12? Not really. Torque and horsepower are comparable to the 6.0-liter V12 in BMW's 760Li. The 6.0-liter V12 in the Mercedes S600, with its twin turbochargers, is substantially more powerful than either the Audi or BMW engines.

The advantage of the W12 lies in the packaging. Despite its extra cylinders, it is no bigger than the typical V8 with less displacement. Indeed, Audi's W12 is actually a bit smaller by overall dimensions than the smaller-displacement V8 in the A8 4.2. The W12 therefore allows Audi to build a 12-cylinder sedan with all-wheel drive. With a conventional V12, there would simply be no space in the engine bay for a differential and other components required to power the front wheels, according to Audi.

Regardless of the packaging advantages, the A8 L 6.0 is a blast to gas. Throttle response is immediate, and it delivers acceleration-producing torque in a wide, flexible band befitting a luxury carmaker's flagship sedan. The W12 pulls hard up to its 6200-rpm redline, and it feels like there's still more power coming when it hits the rev limiter. Moreover, the revs translate to executive-class thrust. Audi reports 0-60 mph times of 5.0 seconds, with top speed governed at 155.

With either engine, the A8's six-speed automatic shifts up or down according to the driver's wishes, deftly sensing how quickly and how hard the throttle is mashed. Upshifts are silky smooth in full automatic mode; in some instances, downshifts could come quicker, but the reserve of torque in either engine more than compensates for any shift lag. This transmission is an improvement in every respect over the A8's previous five-speed automatic. It helps the A8 achieve better fuel economy with the improved acceleration, and V8-powered variants are no longer saddled with a federal Gas Guzzler Tax.

The automatic also features Porsche's Tiptronic system, allowing the driver to slide it into a manually controlled mode. Manual shifting is never necessary, because the transmission is quite responsive in the automatic mode, but it can be a whole lot of fun. Here, however, we lodge a small complaint. Even in manual mode, the transmission will shift up at high rpm, rather than holding the selected gear. That seems to defeat the purpose of giving the driver "manual" control to begin with.

The A8 features adaptive air suspension at all four corners, and it's a bit more sophisticated than the rear air shocks that could be inflated on 1970-vintage American station wagons. Four settings are available, selected electronically with the MMI. There are genuine differences in ride and handling with the basic Comfort and Dynamic settings, but neither is uncomfortably firm nor disappointingly mushy.

In the Comfort mode, the A8 rides at the normal ride height (120 millimeters or 4.7 inches). "Comfort" might suggest a cushy, mushy ride, but that's not the case. Even on a narrow, undulating Kentucky backcountry road, we found the suspension well controlled with Comfort selected, yet still smooth, compliant and comfortable. Switching to the Dynamic mode lowers the suspension by 20 mm (about three-quarters of an inch). You might think Dynamic is buckboard firm, but we found it quite comfortable and compliant, though tuned for sporty handling and more aggressive driving. Both modes operate at all speeds, or you can switch to the Automatic mode. Here the system tailors the suspension damping to conditions and the way you're driving, automatically lowering the car at 75 mph. This is usually the best setting, as the system continuously matches the ride and handling to the situation, and does a good job of it. The ride is smooth and supple, without the slightest sensation of floating or wallowing. Lastly, there is the Lift mode, which raises the suspension 25 mm (about an inch) above the normal ride height. Lift is a good setting for gravel roads, snow, nasty driveway or garage transitions and other situations that call for a raised ride height. Exceed 62 mph in Lift mode and the suspension automatically lowers to the normal ride height.

Besides offering excellent traction in slippery conditions, the A8's quattro all-wheel-drive system improves stability when cornering, whether under full-throttle acceleration or when the driver lifts off the gas suddenly in the middle of a turn. Quattro also eliminates torque steer, that pulling sensation on the steering wheel that powerful front-drive cars often exhibit under acceleration.

Despite its length and substantial weight, the A8 is impressively agile, and bears up well under truly aggressive driving. The steering is sharp and precise, providing excellent communication between the tires and the driver. One key to this big sedan's excellent handling and ride quality is its rigid aluminum space frame. The frame resists flexing and lets the suspension do all the work, which is how it's supposed to be. That's why the A8 delivers such a nice balance of fine handling and ride comfort. Driven to the limit in a corner, it understeers a bit, tending to push toward the outside edge of the pavement. To counter this, the driver simply lifts a little from the throttle, and the front tucks in and tracks through the turn. It works beautifully.

The A8's brakes are easy to modulate for smooth stops, and powerful enough for repeated hard braking from high speeds without fading. The electronic brake-force distribution (EBD) re-proportions braking force from rear to front as weight inevitably shifts forward during braking. If needed, Brake Assist will sense a panic stop and apply maximum braking even if the driver hasn't fully depressed the pedal. The A8 exhibits very little nose-dive during braking and absolutely no drama in the hardest stops. It simply stops straight and true, allowing the driver to maintain steering control in virtually all circumstances.

The A8's Differential Lock helps assures stability even while turning under hard acceleration. An electronic stability program (ESP) compares vehicle behavior against driver input, and uses the antilock brakes and traction control to correct a skid or slide. Add quattro all-wheel drive, and the A8 will do everything physically possible to keep you heading where you want to go. In an emergency situation, just remember to stand on the brakes, don't relieve pedal pressure, and look and steer where you want to go.

With each new model introduction, Audi further dispels any lingering perception that it's not a Tier 1 premium brand on par Mercedes and BMW. Like the Mercedes S-Class and the BMW 7 Series, the Audi A8 is fast, roomy, luxurious and exceptionally comfortable. It rides like a luxury car, yet it's taut and handles like a sports sedan should you decide to drive it more aggressively. Loaded with innovation, the A8 is a thinking man's luxury sedan, more progressive, less traditional than a BMW or Mercedes. It's elegant but not arrogant, indulgent without being excessive. It's priced a little lower than comparable sedans from BMW and Mercedes-Benz, yet gives up almost nothing to either.

V8 or 12-cylinder? In Germany, where the autobahn beckons with no speed limit, that would be an easier choice, assuming money is no object. In our land, the 12-cylinder's advantage is image as much as it is functional. The $45,000 price premium compared to the V8 makes for expensive image, no matter how much disposable income you have. Nonetheless, if you want a 12-cylinder sedan with all-wheel drive, you can't choose an S-Class or 7 Series, because neither Mercedes nor BMW offers one. And even if they did, the A8 L 6.0 quattro would be an excellent choice.