PALISADES, NY – BMW AG has many tricks up its corporate sleeve in the area of product development. One vehicle may showcase an all-new engine or transmission or an innovative approach to steering or chassis control, or all of the above.

But the new 5-Series Gran Turismo has none of those. Instead of offering a technical advancement, this aerodynamically designed coupe-like sedan is all about packaging and, to an extent, recycling proven attributes on vehicles already in production.

Although “5-Series,” is part of its name, the Gran Turismo actually shares more architectural underpinnings with the flagship 750i sedan – and handles with the same confidence, too.

The two vehicles have the same wheelbase (the Gran Turismo is 3 ins. [7.6 cm] shorter overall) and share the identical twin-turbo 400-hp V-8, steering system and 8-speed transmission. Interior design continuity also carries over from the 7-Series.

But behind the back seat, the Gran Turismo is something the 7-Series will never be: a hatchback. Bavarian engineers are probably spitting out their coffee at the mere suggested linkage between the brand’s most luxurious sedan and a term unofficially banished from America’s automotive lexicon years ago.

But let’s call it what it is: An expensive car daring to offer the versatility enjoyed by youthful buyers of Japanese subcompacts 30 years ago.

Not that there’s anything wrong with that. The magic of the Gran Turismo is it doesn’t have to be a hatchback. It has both a trunk and a fully functioning liftgate.

The trunk opens and closes like any other, but the opening is smaller and vertical, resembling the business end of a large-mouth bass. Raise the liftgate, and the back window goes with it, along with the entire back of the car above the bumper, including the trunk lid and all the mechanical parts, allowing it to open and close. BMW calls it a “bi-modal trunk” or “dual-access tailgate.”

Need to bring caviar and cognac to the country club or a tray of hors d’oeuvres to the yacht club? The trunk is all you need. Why make a scene by raising the entire liftgate?

The rebellious sort, however, might say to heck with convention, arriving at the polo field unafraid to press the button on the key fob to raise the motorized liftgate, providing easy access to an ample hold for gear. The flat floor makes for easy loading and unloading of cases of pinot noir from the vineyard.

Italian auto makers first coined the term Gran Turismo (Grand Touring) in the 1950s for stylish 2-seat sports cars with luxurious amenities. The hatchback body style was essential to provide luggage room for two, for weekend get-aways.

BMW expands on the concept by keeping the coupe-like profile but adding two more doors (all four aluminum lightweight doors have frameless windows) and a back seat.

Standard in the second row is bench seating for three, with a 40-20-40 split for selective fold-down. Optional is luxury rear seating for two, which offers adjustable power bucket seats (with power head restraints) separated by a center console.

Although comfortable, the luxury seating for two in the rear creates an ergonomic challenge because the center console extends beyond the seat cushion, blocking access to climate controls placed on the back of the center console from the front row.

Product planners anticipate most models will be equipped with the standard 3-passenger rear bench partly because most customers for the Gran Turismo are expected to be women with children.

Despite the raked roofline at the rear of the Gran Turismo, the back seat is exceptionally spacious, with more headroom and nearly 3 ins. (7.6 cm) of additional legroom when compared with the 750i. The entire back seat also slides fore and aft nearly 4 ins. (10 cm).

Further separating the trunk from the cabin is a variable partition that folds flat when maximum storage is needed. BMW engineers aren’t fooling when they claim the acoustic partition renders the interior as quiet as that of a sedan. With the partition up, the Gran Turismo is as quiet as a bank vault, or a 7-Series.

The car also shares with the 7-Series its active steering system, priced as a stand-alone option at $1,750. As the driver steers the front wheels at low speeds, the rear wheels turn in the opposite direction, reducing the turning circle more than 2 ft. (0.6 m) and making less work for the driver.

’10 BMW 550i Gran Turismo
Vehicle type Front-engine, rear-drive, 5-passenger, 5-door sedan
Engine 4.4L twin-turbo DOHC all-aluminum DI V-8
Power (SAE net) 400 hp @ 5,500-6,400 rpm
Torque 450 lb.-ft (610 Nm) @ 1,750-4,500rpm
Transmission 8-speed automatic
Wheelbase 120.7 ins. (307 cm)
Overall length 196.8 ins. (500 cm)
Overall width 74.8 ins. (190 cm)
Overall height 61.4 ins. (156 cm)
Curb weight 4,938 lbs./2,240 kg
Base price $64,725
Fuel economy 15/21 mpg (16/11 L/100 km)
Competition Audi A7 Sportback (expected fall 2011), A6, A8 and Q7; Mercedes E-, S-, M- and R-Class; Lexus LS
Pros Cons
7-Series DNA Must wait for new I-6
Liftgate functionality Hatchback imagery
Spacious second row HVAC controls blocked

Above 30 mph (48 km/h), the front and rear wheels steer slightly in the same direction via a servo motor acting on track rods, enhancing stability during lane changes and improving comfort for rear occupants by reducing lateral forces.

The 4.4L twin-turbo direct-injection V-8, also shared with the significantly heavier truck-based X6 sport activity vehicle, delivers more than enough punch to propel the 4,938-lb. (2,240-kg) Gran Turismo. It can sprint to 60 mph (97 km/h) in 5.4 seconds.

That’s a tad slower than its sibling, the 750i, which is nearly 400 lbs. (181 kg) lighter. The vehicle trip computer calculated disappointing fuel economy of 14.7 mpg (16 L/100 km) after a 138-mile (22-km) route of mixed driving. A later highway jaunt delivered an impressive 23.5 mpg (10 L/100 km).

But a twin-turbo V-8 can deliver only so much efficiency, so in spring BMW will offer the 535i Gran Turismo with an upgraded version of its excellent 3.0L direct-injection twin-turbo inline-6 (codenamed N54), which earned three consecutive Ward’s 10 Best Engines honors from 2007 to 2009.

The output of the revised I-6 (codenamed N55) will be the same as it is currently – 300 hp and 300 lb.-ft. (407 Nm) of torque. But the induction setup changes from two separate turbochargers to a twin-scroll unit packaged in one housing. The torque peak arrives earlier, at 1,200 rpm, compared with 1,400 rpm for the current N54.

With the new induction strategy and a fully variable third-generation Valvetronic valvetrain, the new N55 is expected to deliver 8% better fuel economy than the N54. BMW says the new I-6 will not replace the old one, and that the N54 will remain in certain applications for the foreseeable future.

In addition to the 6-cyl. Gran Turismo, BMW will launch next spring an all-wheel-drive version. First out of the chute is the rear-wheel-drive V-8 model, arriving in showrooms this month with a base price of $64,725, which is modest by 7-Series standards. The price includes $825 destination and handling charges.

The Gran Turismo also is the first BMW in the U.S. to offer regenerative braking. Instead of running continuously, this unique alternator charges the battery only when the vehicle is decelerating or braking. Otherwise, it freewheels, drawing virtually no power from the engine and boosting fuel efficiency 2%. A more powerful battery accommodates the less frequent charging.

A range of options on the Gran Turismo quickly can boost the bottom line: $4,200 for the sport package; $3,950 for the power-assisted luxury rear seating package; $2,950 for ventilated seats; $2,600 for night vision with pedestrian detection; $2,200 for the rear-seat entertainment system; and $1,300 for the head-up display. The ski bag is an extra $150.

The auto maker isn’t discussing sales projections. Through November, it has sold 36,195 5-Series and 8,205 7-Series sedans in the U.S., according to Ward’s data.

Both the Gran Turismo and 7-Series come from BMW’s plant in Dingolfing, Germany, near Munich. Despite its connections to the 7-Series, BMW associates the Gran Turismo with the 5-Series because of its price and sedan body.

Plus, the all-new 5-Series, soon to arrive, shares its suspension design and technology with both the Gran Turismo and 7-Series.

The Gran Turismo is a lot of things – a luxury car, family hauler, sporty performer and functional ute. And it’s an affordable way to get 7-Series technology.

Yes, the swoopy back end resembles that of the X6, but the Gran Turismo rides lower and feels much more car-like.

Both vehicles have a liftgate, enabled by the “fastback roofline” as BMW refers to it in press materials.

That’s a fancy way to say “hatchback.”

tmurphy@wardsauto.com