The 2012 GMC Yukon is available as a 4-door, 7-seat sport utility. Starting at $40,085, the 2012 GMC Yukon SLE 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 2012GMCYukonDenali 4x2 , priced at $ 55,010 , is powered by a 6.2L , 8 - cylinder engine mated to an automatic transmission that returns an EPA estimated 14-mpg in the city and 18-mpg on the highway.