The relationship between the Subaru Legacy and its Outback trim level historically has been somewhat awkward.

The Outback, traditionally 70% of Legacy mix, has been more upscale and more off-road capable, while the Legacy — especially the weak-selling sedan — was relegated to also-ran status, even though the trend-setting Outback originally sprang from the Legacy platform.

This undesirable differentiation came despite both sharing the same powertrain: Subaru's trademark horizontally opposed boxer engines and symmetrical all-wheel drive. With the all-new, '05 generation, however, Subaru of America Inc. gives the non-Outback Legacy its due.

Now, the Legacy and its flashier Outback big brother are more varied on paper, but difficult to tell apart behind the wheel.

Officially, the Outback becomes classified, for corporate average fuel economy calculations, as a truck for the first time, while the Legacy remains a car. But the new Legacy is so refined, so performance-oriented, that one can't help but confuse the new car with the upper trim level Outback.

The new Legacy is big in Japan, where it recently achieved best-selling midsize car status and was named Car of the Year. And while Legacy plays second fiddle to the Outback in the U.S., Subaru is expecting sales of the attractive sedan to gain ground.

Both the Legacy sedan and wagon come in four trim levels: the 2.5i, 2.5i Limited, 2.5 GT and 2.5 GT Limited.

Both the 2.5L naturally aspirated and turbocharged DOHC H-4 engines are new, and Subaru engineers labored to reduce engine weight, while retaining power. The result: 165 hp in the naturally aspirated version and 250 with the turbo.

Mated to a choice of transmissions (a 4-speed automatic, 5-speed automatic or 5-speed manual), the engines seem remarkably smooth — even the normally rough-around-the-edges turbo.

The Legacy, whose redesign is significant — if evolutionary — from the last generation, is larger overall. The wheelbase is 105 ins. (267 cm), up from 104 ins. (264 cm), and the length has grown by almost 2 ins. (5 cm) to 186 ins. (473 cm) for the sedan and 189 ins. (479 cm) for the wagon. Subaru says the body structure uses more aluminum and high-strength steel — part of a comprehensive weight-reduction objective.

The vehicle rides on a new version of Subaru's ring-shaped “reinforcement frame” safety structure. Four-wheel-disc antilock brakes with electronic brake-force distribution, along with symmetrical AWD, are included in a thorough list of standard features.

Overall refinement prompted journalists test driving the Legacy in Las Vegas to muse whether Subaru's new level of perceived quality is straying too far from brand identity. But Subaru isn't worried about being “too refined,” nor is the wagon specialist concerned about getting too truck-like.

Its newer, truck-like capabilities mark the most significant changes to the Outback.

With the official “truck” classification, Outback receives an extra 1.8 ins. (4.6 cm) of ground clearance — for 8.4 ins. (21 cm) on the 2.5i and 3.0 R trim levels and 8.7 ins. (22 cm) on the 2.5 XT trim model — making the cross/utility vehicle higher than some truck-based SUVs, Subaru says.

Paired with improved angles of approach and departure, the new Outback is more off-road capable than its predecessor. But the change doesn't come at the expense of Subaru's sense of balance.

The engine rides lower than in the previous generation, giving it a lower center of gravity for increased stability and more car-like handling, engineers claim.

The Outback comes with a choice of three engine variants: the 168-hp 2.5L H-4, which powers the 2.5i and 2.5i Limited trim levels; the same 2.5L aided by a turbocharger for 250 hp in the 2.5 XT; and a newly designed, more lightweight H-6 with 80% new components, variable valve timing and an active valve lift system, which also produces 250 hp.

The turbocharged 4-cyl. and new H-6, though boasting identical horsepower, are designed to appeal to different buyers, Subaru says. “Yes, they both make 250 hp, but they do so in a different way,” says Martyn Harding, SOA product planner.

Specifically, the turbocharged 4-cyl. brings more torque — 250 lb.-ft. (339 Nm) as opposed to 219 lb.-ft. (297 Nm) with the 6-cyl. — to appeal to a younger, more performance-oriented driver.

The H-6-powered 3.0 R Outback model is more refined and will serve as the flagship for a vehicle line that's striving for a premium stance — mostly through higher quality interior materials and more standard features, from heated mirrors across the lineup to a mahogany and leather-wrapped steering wheel on the 3.0 R.

The 3.0 R also gets an exclusive application of Subaru's AWD system that features variable torque distribution integrated with vehicle dynamic control, which is designed to help the driver maintain direction and stability under a variety of driving circumstances.

It also incorporates an all-wheel, all-speed traction-control system to reduce wheelspin — also helpful for off-roading.

A possible drawback: The vehicles are pricey: A top-level Outback can bump up on $33,000. But Subaru says that's part of its strategy of differentiation.

“We cannot sell at the lowest price,” says a top Subaru executive. “We cannot discount the brand.”

The strategy instead is to attract new customers who appreciate the niche auto maker's engineering prowess — and are willing to pay a premium for niceties such as AWD, which quickly is becoming a performance-car standard.

And, as Subaru guarantees, customers will be getting what they pay for.

'05 Subaru Legacy 2.5 GT

Vehicle type: Front-engine, all-wheel drive, 5-passenger 4-door sedan

Engine: 2.5L (2,457 cc) turbocharged DOHC H-4, aluminum block/aluminum heads

Power (SAE net): 250 hp @ 6,000 rpm

Torque: 250 lb.-ft. (339 Nm) @ 3,600 rpm

Compression ratio: 8.2:1

Bore × stroke (mm): 99.5 × 79

Transmission: 5-speed manual

Wheelbase: 105.1 ins. (267 cm)

Overall length: 186.2 ins. (473 cm)

Overall width: 68.1 ins. (173 cm)

Overall height: 56.1 ins. (142 cm)

Curb weight: 3,300 lbs. (1,498 kg)

Market competition: Audi A4; Acura TSX; Honda Accord; Mazda6; Toyota Camry