I bought a 2011 xlt 3.7L back in january replaced a s-10. The best move I ever made the s-10 got about 18.3mpg I'm now averaging about 20.8 combined. If your worried about the 3.7 not having enough power, don't theres plenty you just have push the pedal alittle harder. My drive to work and back is around 64 miles and truck does find. I must admit I don't run it hard but I average 60 mph. One thing to note the tach goes to 7000 and theres now red line. Theres plenty of engine I haven't explored yet. Don't need to go that fast in a truck.