Hi, i really hesitate which pickup to buy . I hesitate between 2010 1500 4x4 with 5.3l extended cab with 8 feet box and 2010 2500hd 4x4 with 6.0l crew cab with 8 feet box the main reason i want a 2500hd is because the 8 feed box and crew cab. I will drive about 8000k mile year 80% of my driving will to go to my cottage with trailer about 1500kg I have to run 350 mile through mountain when I go to my cottage. which mpg should I get with a 6.0l versus a 5.3l for my use ? is the 2500hd crew cab vs the 1500 extended cab will worth the extra money I will spend on fuel ? Thank a lot Christ !