My family is looking to add another vehicle with more room. I currently have a 2005 Yukon xl 1500. So, why not have a fleet of "ultimate transport vehicles"? I may have found a good deal on a 2000 Yukon XL 2500 with a 6.0L and 4:10 rear end. Does anyone know what MPG I can expect out of it? With the 1500 (5.3L 3.73 gear) I get about 20mpg on the highway and 16 in the city. I know that the 2500 will not do that "well", but what can I expect?