The long-wheelbase TrailBlazer EXT is available in two trims, the LS and LT. Both 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. A four-wheel drive option is available on all models. The TrailBlazer EXT LS and TrailBlazer EXT LT are equipped similarly to their standard-wheelbase counterparts. The EXT LS models come standard with a HomeLink transmitter, fog lamps, 17-inch wheels, and other upgrades. The Vortec 5300 5.3-liter V8 which powers the vehicle delivers 300-horsepower and 330 pound-feet of torque. All EXT models come standard with a four-speed automatic transmission.For 2005, the Vortec 5300 V8 with its Displacement on Demand technology promises about 8 percent better fuel economy than the engine it replaces.