SAN FRANCISCO: Introducing
the 2003 Audi A4 & A6 series with CVT, the Multitronic continuously variable
transmission. The bottom line is great value in a car that combines the latest technology
in an upscale German-built sports sedan.
San Francisco: For several decades the continuously variable transmission
(CVT) has been touted as the transmission of the future. The difference between a geared
transmission, either manual or automatic, and a CVT is that the latter provides
essentially an infinite number of gear ratios versus four, five or at most, six ratios.
This allows the engine to always supply power to the wheels in the rpm range that gives
the best performance and/or fuel economy and do it smoothly and seamlessly without any
shift points. Besides giving better fuel economy, typically a 5- to 15-percent improvement
over a traditional automatic transmission, CVTs are simpler. The latter is becoming more
important as electronically automatic transmissions become ever more complex and
expensive. Indeed, it now cost almost as much to manufacture an automatic as building an
engine. For the consumer, less complexity mean fewer things to go wrong and lower
The CVT is far from new having been invented by Dutch engineer, Van Den Brink in the
1950s. A CVT first appeared in the tiny Dutch-built DAF 600 in 1959. Named
"Variomatic" it was used in DAFs until 1975 when Volvo purchased DAF. Volvo
carried on production of DAF-designed cars until 1991 and Variomatic continued to be
offered as an option. CVTs has been used several other cars such as the Subaru Justy,
Honda Insight and Toyota Prius hybrid electric vehicles, the Saturn Vue SUV and even the
new BMW-built Mini.
Unlike a regular automatic transmission, which does the shifting with gears and fluid
couplings, the CVT uses a simple set of pulleys connected by a belt. Each pulley is split
in half, like the bottoms of two saucers. As the pulleys are parted, the belt rides closer
to the center for at low vehicle speeds. When the pulley halves are squeezed together, the
belt moves toward the outer edge of the pulley for higher speed operation. With moveable
pulleys on either end of the belt the power transmission can vary in infinitesimal
amounts. That is why the CVT gets the name continuously "variable".
The CVTs challenge for many years is that they were limited in the amount of power they
could transmit, thus they were used only in low-power, sub-compact cars. Audi engineers
overcome this limitation by replacing the belts with a vanadium-plated, steel, link-plate
chain used in conjunction with the hydraulically adjustable sets of beveled split pulleys.
Using feedback from the engine management system, the Audi CVT selects the precise gear
ratio to delivers the ideal amount of torque to match load conditions at any given moment.
The Audi multitonic® CVT is now offered in the A4 1.8T, A4 3.0 V6 and A6 3.0 V6. The
1.8T is a 1.8-liter turbocharged four-cylinder engine that produces 170-horsepower at 5900
rpm and 166 pound-feet at 1950 rpm. The normally aspirated 3.0-liter V6 produces
220-horsepower at 6300 rpm and 221 pound-feet of torque. The multitonic CVT is now only
available with Audi FrontTrak front-wheel-drive. Audi engineers are still working on
adapting a CVT for use with Audis quattro, all-wheel-drive system. This means you
can order an Audi A4 and Audi A6 sedan as well as the A4 Cabriolet with multitronic®.
Avant station wagon models are offered only in quattro form.
And how well does multitronic® work? Only the very observant will notice the
difference between it and todays smooth automatic transmissions. Listen and feel
carefully and you might notice a momentary hesitant at launch, but shifts are velvet
smooth. Indeed, the Audi designers artificially programmed shift points in. Otherwise, the
CVT would work electric car-like, so Audi felt drivers would prefer a more conventional
feel in an automatic tranny. Like many automatics today, there is a manual shift mode. In
this case like a six-speed manual. Control is either via the console mounted shift lever,
or buttons located on the steering wheel like in a Grand Prix racecar.
I drove both the A4 1.8T and the A4 3.0 V6. Surprisingly, even with a 50-horsepower
difference, I found that it would take a stopwatch to tell the difference. The
turbocharger on the 4-cylinder does its job so well. According to Audi, the engines are so
fuel-efficient and clean that they qualify for California's Ultra Low Emissions Vehicle
certification. The fuel tank holds 18.5 gallons, great for long distance cruisers
mpg city/29 mpg hwy 19 mpg city/27 mpg hwy
5-speed Manual 22 mpg city/31 mpg hwy
The rest of the package is typically Audi, meaning great. The styling, which was new
for 2002, is handsome and a bit understated. Handling and ride quality is excellent,
definitely German tight and taut. I made a lengthy trip with the A4 1.8T and was not a bit
tired after 3-4 hour stints behind the wheel. Instrumentation, controls, interior room and
cargo space bring no complaints.
Even these "entry level" Audi feature advanced technology like
computer-assisted traction control and an electronic stabilization program (ESP) for skid
control. Other standard equipment includes automatic climate control system with dual-zone
thermostats and carbon micro-filtration. There is also an AM/FM/CD sound system with a
six-CD changer in the dash. Safety-wise there are dual front airbags, front-seat side
airbags, curtain-style head protection airbags and anti-lock brakes with Brake Assist.
Significant options include Xenon headlamps, rear side-impact airbags, OnStar, Bose
200-watt premium audio system, and a sunroof. Prices for the A4 1.8T start at $26,760 and
$32,250 for the A4 3.0 V6.
The bottom line great value in a car that combines the latest technology in an
upscale German-built sports sedan. By Bill
Siuru © AutoWire.Net - San Francisco
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Column Name: The transmission of the future here today
Topic: The 2003 Audi A4 with CVT
Word Count: 1032
Photo Caption: The 2003 Audi A4
Photo Credits: Audi Internet Media
Series #: 2002 - 37
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