The 2005 GMC Envoy is a 4-door, 5-passenger sport-utility, available in 4 trims, ranging from the SLE 2WD to the SLT 4WD. Upon introduction, the SLE 2WD is equipped with a standard 4.2-liter, I6, 275-horsepower engine that achieves 16-mpg in the city and 21-mpg on the highway. The SLT 4WD is equipped with a standard 4.2-liter, I6, 275-horsepower engine that achieves 15-mpg in the city and 20-mpg on the highway. A 4-speed automatic transmission with overdrive is standard on both trims. The 2005 GMC Envoy is a carryover from 2004.