The heavily re-worked 2010 Buick LaCrosse presents a new trim level, two new engines, and a new transmission to go along with some significant styling changes. The five-passenger midsize LaCrosse sedan is also the first U.S. auto to be constructed on GM’s touted Epsilon II platform. Thus ride and handling, already a high point with last year’s LaCrosse, are improved and refined even further.

For 2010, the Buick LaCrosse will be delivered in three trims, CX, CXL, and a new, top-shelf CXS that replaces the misnamed Super trim. All trims are offered with standard front-wheel drive (FWD), though the CXL trim will be available with an optional all-wheel-drive (AWD) configuration. Exterior changes for the 2010 LaCrosse include a more aggressive front fascia, removal of the trademark “portholes” from fenders to hood, larger wheel-arc brows, and a Euro-style sweep to the roofline and side/fender panels. Inside, a completely reconfigured dashboard and center console arrangement is evocative of a Lexus, or perhaps Infiniti, a look that Buick makes no apologies for and indeed seems to cultivate.

Both the 3.8-liter V6 and 5.3-liter V8 have been replaced by, respectively, a 255-hp, 3.0-liter V6, and a 280-hp, 3.6-liter V6. The 3.0-liter V6 will equip the base CX and midlevel CXL trims, while the CXS trim will carry the 3.6-liter V6. Both engines will be managed by a new-for-2010 six-speed automatic transmission that will allow the 3.0-liter to generate 211 lb-ft of torque and the 3.6-liter some 260 lb-ft. The six-speed automatic transmission replaces a much-maligned four-speed automatic. Mileage estimates are not available yet for the 2010 LaCrosse, but each of the V6s is direct-injected, thus fuel efficiency ought to be somewhat better than last year’s 17/28 mpg.

Standard comfort, convenience, and appearance features for the 2010 Buick LaCrosse CX trim are expected to include 17-inch alloy wheels, climate control, a single-CD player, and cruise control. The CXL trim is expected to add dual-zone climate control, leather-appointed heated front seats, LED turn signals mounted in the outside mirrors, fog/driving lights, available AWD, and 18-inch alloy wheels. The top-line CXS is expected to add leather upholstery, a real-time dampening suspension system, and chrome-plated 18-inch wheels, with 19-inch six-spoke wheels an available option. A power sunroof and DVD navigation system are expected to be among the options available with the CX trim.

Safety features expected to come standard with the 2010 LaCrosse include four-wheel disc ABS with electronic brakeforce distribution, side airbags, front and rear airbags, traction and stability control, backup sensors, a lane-departure warning system, and the Onstar post-collision safety system.

Buick has addressed a number of complaints concerning the ’09 Buick LaCrosse, including replacing the four-speed automatic, losing the aging 3.8-liter V6, and adding front fog/driving lights. Issues with reliability, peeling exterior paint, and rear-seat legroom in the ’09 LaCrosse have yet to be addressed. Most owners of the ’09 LaCrosse, however, lauded the mileage they were getting with the venerable V6, the LaCrosse’s looks, and especially its ride and handling characteristics. Each of these aspects should be even better for 2010.