I have a '03 f350 5.4 4x4 crew cab long bed. 98k miles. All stock except for K&N filter and Predator tuner. The tuner woke this truck up so much that it does not even seem to be the same truck. Much better throttle response. I went on a 180 mile one way trip to buy a utility work top for my truck. On the way there I got 17.6 mpg. With the top on I got 13 on the way back. Definetly need to take the top off for trips! Tuner was worth every penny ($169). I think the truck was getting around 10-11 before i installed it.