The 2012 GMC Yukon XL 2500 is available as a 4-door, 7-seat sport utility. Starting at $45,045, the 2012 GMC Yukon XL 2500 SLE 4x2 is powered by a 6.0L , 8 -cylinder engine mated to an automatic transmission that returns an EPA estimated 10-mpg in the city and 16-mpg on the highway. The top of the line 2012GMCYukon XL 2500Commercial Fleet 4x4 , priced at $ 47,885 , is powered by a 6.0L , 8 - cylinder engine mated to an automatic transmission that returns an EPA estimated 10-mpg in the city and 15-mpg on the highway.