The 2011 Acadia is available in three trims: the base SL, the mid-range SLE, the uplevel SLT and the luxury Denali. Each is available with either front- or all-wheel drive. All trims are powered by a 3.6L V6 engine with direct fuel injection, which delivers 288 horsepower and 270 pound-feet of torque at 3400 rpm. A 6-speed automatic transmission is the only transmission available. The 2011 Acadia comes with variable-effort rack-and-pinion steering and a low center of mass for stable cornering. The 4-wheel independent suspension allows for a compliant ride and a maximum towing capacity of up to 5,200 pounds, comparable to some truck-based mid-size SUVs. Safety was given priority in the Acadia's engineering and feature list. Stabilitrak electronic stability control with rollover mitigation technology, is standard, as is anti-lock brakes, panic brake assist and six airbags, including head-curtain side bags that cover all three rows of seating. An extremely roomy interior is one of the Acadia's strengths. The three rows provide seating for up to seven or eight, depending on whether buyers opt for captain's chairs or 60/40-split bench seat for the second row. The bench slides fore and aft for easier access to the third row or added seating space. There are plenty of bins and cubbies all around, as well as ten cup holders. The Acadia's look is quite different between trims, thanks to a wide range of wheel offerings. SL models get 18-inch wheels, the SLE upgrades to 18-inch machined aluminum wheels, SLT trims receive 19-inch machined aluminum wheels. Denali trims come with chrome 20-inch wheels. Denalis also get trim-specific fender flares, rocker moldings, sill plates plus a special grille. The base SL models are well-appointed and include keyless entry, cruise control, front and rear air conditioning and MP3-compatible CD audio. The SLE trim adds fog lamps, an upgraded 6-speaker stereo, power-adjustable front seats, a leather-wrapped steering wheel and a rearview camera system. The SLT trim adds climate control, 3-zone air conditioning, premium Bose sound system, auto-dimming rearview mirror, power-adjustable and heated side mirrors and a power liftgate. The top-of-the-line Denali adds a heavy-duty cooling system and trailering equipment, dual panoramic sunroofs, quiet sound insulation, heads-up display and automatic up/down power windows. Noteworthy options include a DVD entertainment system, leather upholstery and a navigation system.