Although it has little in common with the concept car by the same name shown at the 2000 North American International Auto Show, the 2006 LaCrosse has been given the task of reviving Buick's fortunes in the under-$30,000 price bracket among sedans. It's a direct replacement for the Regal and its budget-oriented Century twin, but a new engine, a higher-quality interior, a longer equipment list and a reworked suspension allow it to move uptown in image.

On the outside, the LaCrosse blends traditional Buick styling cues -- a softly curved hood and a vertical-slat grille -- with modern-day trends. The pull handles on the doors make the LaCrosse look like a contemporary of competing midsize sedans -- always a plus for a Buick car. Inside, designers have equipped the new sedan with a clean control layout, interlocking analog gauges and liberal amounts of wood grain trim. The LaCrosse also benefits from the same kind of "QuietTuning" that went into the Rainier, and to that end, it has plenty of sound-deadening material in all the key areas, acoustical laminate on the glass and tightened body panel gap tolerances.

The engine lineup includes a 200-horsepower, 3.8-liter (3800) V6 is the base engine. Exclusive to the CXS model is a 3.6-liter DOHC V6 that makes 240 hp and 225 pound-feet of torque. The Buick LaCrosse rides on the same front strut/rear tri-link suspension as its predecessor, but approximately 80 percent of the components were retuned to balance the supple ride quality that traditional Buick car buyers expect against the controlled handling that mainstream midsize sedan buyers expect.

In recent years, the Regal and Century ceased to be major players in the midsize sedan segment -- outside of rental car fleets, anyway. And compared to these cars, the LaCrosse is a few steps up in performance, quality and refinement. In spite of its all-new name, though, the 2006 Buick LaCrosse is built on an old platform. Alongside competitors like the Chrysler 300, the LaCrosse's handling characteristics are crude and its backseat cramped. Add in a short standard equipment list and it seems Buick is facing an uphill battle once again.

The Buick LaCrosse is available in sedan form only in one of three trims -- CX, CXL and CXS. The CX includes the basics like cloth upholstery, a power driver seat, a six-speaker CD stereo and OnStar. The CXL adds leather upholstery, automatic climate control, a 60/40-split rear-seat back, uplevel exterior trim and alloy wheels. The CXS builds upon the CXL with a more powerful V6, a sport-tuned suspension and larger alloy wheels. Among the available equipment are a handy remote-start feature, rear parking assist, an MP3-compatible stereo and satellite radio.

A 200-horsepower, 3.8-liter V6 powers the CX and CXL models. Exclusive to the CXS model is a 3.6-liter DOHC V6. Aided by continuously variable valve timing, it produces 240 hp and 225 pound-feet of torque. A four-speed automatic transmission is standard on all models.

Side head curtain airbags are standard, along with OnStar and four-wheel antilock disc brakes. An optional stability control system is available only on the CXS. A reverse-sensing system is optional. In NHTSA crash tests, the Buick LaCrosse earned a five-star rating (out of a possible five) for its protection of the driver and front passenger in frontal impacts. The car also has a three-star rating for its performance in the side-impact test, though the vehicle tested did not have this year's standard side curtain airbags.

On the highway, the 2006 Buick LaCrosse rides smoothly and soaks up the bumps without transferring the impact to occupants -- the mark of any good full-size sedan. But there's no hiding the aging chassis when you hit a winding stretch of road, where the body rolls plenty and the steering feels numb. Although noisy, the base V6 in CX and CXL models offers decent power and good fuel economy. Still, we feel the CXS is a better choice, as its refined, overhead-cam V6 provides a broad power band.

The Buick LaCrosse is offered in both five- and six-passenger seating configurations. The broad, flat seats are easy to slide into, but lack support for longer adults. A tilt steering wheel is standard on all models, and CXL and CXS models include a telescoping function as well. Rear-seat legroom is tight for adults. The dash design is simple with one long expanse of faux wood and an easily readable set of gauges right in front of the driver. The fake wood isn't bad, but competitors do it better. More troublesome are the cheap adjustable vents and the brittle plastic on the center console. All of the controls are within easy reach, but there are way too many small buttons of similar size. There is plenty of storage in the cabin, though, and the trunk measures a healthy 16 cubic feet.