By Jim Meachen and Ted Biederman

Perhaps one of the biggest yet overlooked story lines of the 2007 model year is Nissan’s new and maybe somewhat controversial transmission decision.

The Japanese auto company has dropped conventional automatics from several models in favor of its version of the continuously variable transmission or CVT. Unlike a conventional transmission, the CVT has no shift points.

It is the only automatic transmission option in the upscale Maxima, the all-new mid-sized Altima and the all-new compact Sentra — the company’s three mainstream sedans that accounted for 420,000 sales in 2005.

The Sentra and Altima can still be purchased with six-speed manuals, but the manual transmission option has been dropped from the Maxima.

The CVT has been used in a variety of cars in recent years, particularly in hybrid models. But this is the first extensive use of the technology by one company. Nissan officials in Canton, Miss., recently told us the primary reason for the CVT conversion was gas mileage.

But a look at the 2006 Maxima specifications shows only a one-mile-per-gallon savings in city driving (21 mpg) for the 2007 edition.

We’re not opposed to the CVT, but some drivers who have become accustomed over the years to shift points may need a few trips around the block to get used to a transmission that never changes gears.

The CVT, which has been used sporadically in vehicles for more than 50 years, continuously adjusts the transmission gear ratios for optimum acceleration and fuel economy.

The first mass-produced car with a CVT was the Subaru Justy in the ’80s. Nissan picked up the Subaru technology for a Japanese-market car in the early ’90s. Honda used a CVT on the 1995 Civic.

Most manufacturers today — including Ford, Volkswagen-Audi, Chrysler and Toyota — use a version of the transmission on a variety of vehicles.

We don’t think the new transmission detracts from the considerable desirability of Nissan’s flagship sedan. But the CVT, along with the elimination of the manual shifter option, takes the last visages of true sportiness out of a sedan once marketed as the “premium four-door sports car.”

The Maxima plays a different role today, serving as Nissan’s luxury-appointed four-door and a viable alternative to such near-full-size sedans as the Toyota Avalon, Buick Lucerne, Chrysler 300 and Volkswagen Passat. And it does a good job in that role offering a powerful V-6 engine, quiet and spacious interior, leather-clad seating, a full range of modern amenities and unique styling that doesn’t quite march to the beat of the most popular drummer.

The Maxima, in the fourth year of its sixth generation, gets some tweaks including a reworked front end treatment featuring a new hood, bumper and headlights. Inside, Nissan designers have reworked the center stack for improved ergonomics.

The New Maxima comes in just two trim levels, the sporty 3.5 SE and the more luxury-oriented 3.5 SL. Several packages can be added to suit the buyer’s taste.

The interior feels spacious. This was apparent the minute we sat behind the wheel. Rear-seat passengers have stretch-out room for their legs. A unique feature, which can be ordered as part of the Elite package, is a rear console flanked by two independent bucket seats. The center position in most sedans is not comfortable and seldom used, so this option may appeal to a large number of buyers. It certainly adds to the luxury mood of the car.

The extra cargo capacity gained by a fold-down rear seat is lost, however, with the rear bucket-seat option. Trunk space is a reasonable 15.5 cubic feet.

The Elite package also includes Bluetooth hands free phone, heated rear seats, a power sunshade on the rear window, auto up and down rear windows and rear park assist.

Another unusual Maxima feature is a large, fixed Sky View glass-paneled roof, which comes as standard equipment on the SL trim level. An optional power glass sunroof can be substituted for $900.

Performance has been a hallmark of the Maxima and the single engine choice is a reworked 3.5-liter V-6 rated at 255 horsepower and 252 pound-feet of torque allows the sedan to live up to the Maxima reputation. Even with the CVT Maxima hasn’t lost any of its edge. In fact, may be fractionally faster — capable of a 0-to-60 run in under 6.5 seconds. It is quick with abundant power for all situations regardless of which trim level you choose.

By our seat-of-the-pants estimation we figure the Maxima a tick or two ahead of the Buick Lucerne V-8 and very close to the Toyota Avalon.

The standard 320-watt Bose system with eight speakers, six-CD changer and MP3 capability should please the most demanding of audiophiles. The sound is rich.

The Maxima is not an inexpensive sedan, but then it offers a large amount of content for a base price of $30,905 in the up-level SL package including a full compliment of side and head curtain airbags. The SE starts at $28,655.

Although we think most people would be satisfied with the standard features, it is tempting to want more including navigation at $1,800 as well as one of two packages that adds on Bluetooth, power tilt and telescoping steering wheel and memory seats. Our SL test car with extras carried a bottom line of $35,515.

Even though the Maxima moves away from the sporty car it once professed to be it is endowed with and has embraced a luxury persona; it is a very desirable alternative to the Toyota, Buick, Chrysler and Volkswagen.

Essentials:

Base price: $28,655; as driven: $35,515
Engine: 3.5-liter V-6
Horsepower: 255 @ 6,000 rpm
Torque: 252 pound-feet @ 4,400 rpm
Transmission: Continuously variable
Drive: front wheel
Seating: 2/3
Wheelbase: 111.2 inches
Length: 194.4 inches
Curb weight: 3,579 pounds
Turning circle: 40 feet
Luggage capacity: 15.5 cubic feet
Fuel capacity: 20 gallons
EPA mileage: 28 mpg highway, 21 city (regular)
0-60: 6.2 seconds (Road and Track)
Also consider: Toyota Avalon, Buick Lucerne, Volkswagen Passat, Chrysler 300

The Good:
•Powerful V-6 engine with good gas mileage
•Roomy interior

The Bad:
•Styling may polarize some shoppers
•Sporting sedan becomes luxury cruiser

The Ugly:
•Another sedan falls victim to the “shiftless” masses.