The long-wheelbase EXT LS and LT are stretched 16 inches between the front and rear wheels to provide a third row of seats for seven-passenger capacity and more cargo room. Four-wheel drive is available on all models. TrailBlazer EXT LS and TrailBlazer EXT LT are equipped similarly to their standard-wheelbase counterparts. EXT LS models come standard with a HomeLink transmitter, fog lamps, 17-inch wheels, and other upgrades. The base engine is the 291-horsepower Vortec 4200, a 4.2-liter inline-6. The Vortec 5300 5.3-liter overhead-valve V8, rated 300 horsepower and 330 pound-feet of torque, is now available as an option. All come standard with a four-speed automatic transmission. The SS comes with GM's LS2 6.0-liter V8 engine, which produces 395 horsepower and 400 pound-feet of torque.For 2006, a new SS model has been added to the Chevrolet TrailBlazer lineup.