For fifteen years, the Outback as all but defined Subaru in the United States. The high-riding wagons have been the perfect vessels for the brand's signature all-wheel-drive system. Through three generations, the Outback formula has effectively remained the same. For the fourth-generation 2010 Outback, Subaru has made the most significant changes so far to its best-known model.

The Sport-Utility Wagon: More of the former, less of the latter.

Subaru had been offering four-wheel-drive station wagons here since the mid 1970s, but it wasn't until 1995 that the company created the Outback as a special model. Essentially an all-wheel-drive Legacy station wagon with extra ground clearance and a rugged, outdoorsy image, the Outback has hewn to the same formula through two successive redesigns, even as it has added more engine options (including a turbocharged four and a six-cylinder) and more luxury features.

For 2010, however, the Outback branches out, using a unique bodyshell instead of borrowing one from the Legacy wagon (which is no longer sold in North America, but is still offered in Subaru's home market). Given free reign to craft an Outback-specific body, Subaru designers evolved the shape away from a pure station wagon and more towards a crossover/SUV--much as they did with the new Forester last year.

As a result, the car is fractionally shorter in length (by 0.8 inch) but substantially taller in height (growing 2.0 inches) and wider (2.3 inches). The larger body provides more passenger room and cargo space. Most significant is the increase in rear-seat legroom, which has been expanded by nearly 4 inches, and is now truly generous even for passengers over six-feet tall. The higher roofline provides lots of headroom as well, and seat comfort--formerly a sore point--has improved. In the cargo hold, a repackaged rear suspension is less intrusive, and maximum volume is up by nearly 6 cubic feet while the height of the load floor remains low.

Still a kin to the Legacy, at least under the skin

Although it no longer uses a Legacy wagon's body, the Outback is still mechanically related to the Legacy sedan, which is also new for 2010. Both cars share four- and six-cylinder horizontally opposed boxer engines, along with a range of available manual and automatic transmissions.

This new Outback, however, loses one of its previous three engine choices. The base 2.5-liter four remains, as does the--now larger--six-cylinder, but the turbocharged four has been dropped (although Subaru still offers it in the Legacy GT). Subaru product planners point to poor sales of the turbo in the outgoing model, although a turbocharged engine's inherent advantage at high elevations would seem to make it a good choice for in mountainous areas where the Outback is so popular.

Two boxers left standing

Like all Subaru engines, the two remaining offerings are horizontally opposed, or boxer, engines. The four-cylinder is essentially the same unit that as before. For 2010, however, its two available transmission choices are new. Where the Outback previously did not offer a manual transmission, it now has a six-speed stick shift as standard on the base and mid-level ("Premium") trim levels. Choosing it saves $1000 over the available automatic, but you give some of that back at the gas pump, as the manual's gas mileage, 19/27 mpg (city/highway), falls short of the automatic's 22/29 mpg.

The reason for the automatic's efficiency is that it's a continuously variable transmission (CVT), which is great for fuel economy but is a little strange when accelerating as it can hold the engine at the optimal rpm rather than allowing revs to rise with the car's speed. There are also shift paddles that allow the driver to effect manual up- and downshifts through six preset ratios. Overall, the 170-hp four is up to the task of moving the relatively lightweight Outback--which is commendably svelte compared to the typically porky crossover--but one occasionally wishes for more grunt during two-lane passes or when climbing the steepest hills.

The Outback's optional six-cylinder engine is larger than before--3.6 liters, up from 3.0. Its 256 hp is a modest increase over the smaller six's 245 hp, but its 247 lb-ft of torque a represents a more substantial jump over the previous 215 lb-ft. Despite the increased displacement, the six--which is paired exclusively with a five-speed automatic--manages to increase both city and highway fuel economy by 1 mpg, to 18 city/25 highway. And unlike its predecessor, it runs on regular fuel. This engine makes easy work of propelling the Outback. Less expensive to run than the old six, and less expensive to buy (the extra cost is slightly lower than before), the six-cylinder could see a greater take rate than its recent average of 10 percent or so.

Both engines are surprisingly quiet--the burbling, boxer-engine patter that has long characterized Subaru four-cylinder engines is suppressed. The Outback is a quiet cruiser overall; Subaru has finally ended its fixation with frameless door glass, and wind noise is notably absent. The front suspension is essentially the same as before with damper struts, but the rear switches from a multi-link setup to A-arms. The ride on the highway is plush, if a bit floaty, with suspension tuning identical for both engines. The steering is slightly quicker in the new car but it's not very linear, with a bit too much gain as one moves off center, resulting in the need for small steering corrections.

Of course, a major component of the Outback image is its ability to venture off-pavement, and that capability is slightly enhanced, as all Outbacks now have 8.7 inches of ground clearance and the front and rear overhangs have been trimmed. For most Outback buyers, "off-road" likely translates to "dirt roads". We bombed down plenty of dirt two-tracks in the mountains of Montana, and the Outback never put a tire wrong. More impressive was the car's body structure, which proved tight and rattle-free despite the pounding.

Other items and innovations

In keeping with its outdoorsy image, the Outback is often shown with bikes, skis, or kayaks on its roof, so it's fitting that a roof rack is standard. An interesting new twist, however, is that the rack's crossbars--which often are sold as an extra-cost accessory or, if they're standard, can't be removed and therefore contribute to wind noise--pivot out from the side rails, where they're stored when not in use. A new Harman/Kardon sound system is available, with a USB port and an iPod input (for those who don't upgrade to the H/K system, and iPod input is available as a dealer accessory). Other new options include navigation, a rear-view camera, and Bluetooth phone connectivity. The parking brake is now electronically activated by a button on the dash, and includes a useful hill-holder feature.

Prices rise and fall.

As before, there are three trim levels, now called base, Premium, and Limited, all three available with either engine. Options are few. Base sticker prices starts at $22,995 plus destination (versus $22,295 for the '09 base car) and top out at $30,005 for the top-spec model (compared to $32,095 previously).

The new Outback looks less like the overachieving wagon that won legions of fans, and more like any other crossover. But its abilities remain and have even been enhanced. Despite looking more like it competition, the Outback is still lighter, more economical, and more off-road capable than most.

2010 Subaru OutbackBase Price range: $23,690-$31,690 (with destination)

Powertrain

Engine: 2.5-liter SOHC H-4Horsepower: 170 hp @ 5600 rpmTorque: 170 lb-ft @ 4000 rpmPowertrain: 3.6-liter DOHC H-6Horsepower: 256 hp @ 6000 rpmTorque: 247 lb-ft @ 4400 rpmTransmissions: 6-speed manual, continuously variable automatic, 5-speed automaticDrive: 4-wheel

MeasurementsL x W x H: 188.2 x 71.7 x 65.7 inLegroom: 43.0/37.8 inHeadroom: 40.8/39.3 inCargo capacity: 34.3/71.3 cu ft (seats up/down)Curb weight: 3386-3658 lbsEPA rating (city/highway): 19/27 mpg (2.5L, 6-speed), 22/29 mpg (2.5L, CVT), 18/25 mpg (3.6L

2010 Subaru Outback