The 2009 GMC Envoy is available as a 4-door, 5-seat sport utility. Starting at $36,535, the 2009 GMC Envoy Denali 4x2 is powered by a 5.3L , 8 -cylinder engine mated to an automatic transmission that returns an EPA estimated 15-mpg in the city and 21-mpg on the highway. The top of the line 2009GMCEnvoySLT 4x4 , priced at $ 35,615 , is powered by a 4.2L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 14-mpg in the city and 20-mpg on the highway.