Three trim levels are available for 2009: the base SL, SLE and SLT. All come powered by a 3.6L DOHC V6 direct-injection engine that makes 288 horsepower and 270 pound-feet of torque, which is spread over a broad rpm range. All engines run through a 6-speed automatic transmission. Configurations with either front- or all-wheel drive are available across the range. The all-wheel-drive system is oriented toward on-road driving and always delivers at least some torque to the rear wheels, applying more when needed for best traction. The system automatically varies the torque split from 90% front/10% rear to as much as 35%/65% when needed for road conditions. The Acadia has a uni-body construction, which is lighter than body-on-frame and allows for better handling and comfort. With a 4-wheel independent suspension--including a space-saving rear-mounted system that helps isolate noise and vibration--the Acadia also has a low center of gravity to give it even sharper handling. Safety features include 4-wheel anti-lock brakes, traction control, antiskid system, front side airbags and side curtain airbags for outboard occupants in all three rows. GM's StabiliTrak stability control system, with rollover mitigation technology, is also standard on the Acadia. The National Highway Traffic Safety Administration gives the 2010 GMC Acadia five of five stars for crashes involving the driver, passenger, side-impact front and side-impact rear. The Acadia comes in either 7- or 8-passenger interior configurations. Each setup has bucket seats in front and a three-passenger, 60/40-split folding third row. The 7-passenger version has two captain's chairs in the second row, while the 8-passenger version has a 3-passenger, 60/40-split bench seat for the second row instead. Both configurations come with a second-row Smart Slide function, where the second-row seat cushion flips up and the seatback slides forward for easier access to the third row. Both the second- and third-row seats fold flat for mixes of the two. Cargo capacity is almost 117 cubic feet with all seats down, and 24 cubic feet behind the third-row seat if all are raised. Towing capacity is 4,500 pounds when properly equipped. Standard on the SL are dual exhaust with chrome tips, tire pressure monitoring system, StabiliTrak, 18-inch alloy wheels, 8-passenger seating, front and rear air-conditioning, full power accessories, cruise control, and a 6-speaker CD/MP3 stereo system with satellite radio. The SLE comes standard with 8-passenger seating, Bluetooth hands-free connectivity, remote start, halogen fog lamps and ultrasonic rear parking assist. The top SLT can be split into 1 and 2 trim levels. SLT1 trim boasts heated mirrors with integrated turn signals, a Bose premium 10-speaker stereo system with 6-disc CD changer, driver information center, heated power front seats and tri-zone automatic power control, while the SLT2 adds and 8-way power driver seat, 20-inch chrome-clad aluminum wheels, and power adjustable, folding, and heated mirrors with auto-dimming. GM's OnStar service is standard on all Acadias for one year, while options packages include ultrasonic rear parking assist, a 6-way power driver seat, leather-wrapped steering wheel and Bluetooth.