Well I just refueled the tank for the first time since I got the new programmer. Fuel milage actually went down to 15.6 hand calculated. I was getting about 16MPG when stock. So I decided to go from level 3 = 160HP to level 2=90 on my programmer. Hooked the programmer up changed the level, PPE froze on me. I unhooked/turned the key off and nothing. Truck would not turn over as it had no program installed. I called PPE on the phone for 20 minutes did not receive very good support. He could not help me! Truck would not recognize VIN # and would not go past that page. After I got off the phone I disconnected the batteries, tried again and nothing, I playing around with the programmer for a few and found return to stock setting and it worked. Went back to stock, then was able to select level two after it was stock. So will see how level two does. I was hoping for at least 17MPG, I don't beat on my truck I drive it normal usually don't go much above 2400RPM! I asked the guy at PPE and he said if the truck had a programmer before that the ECM could be no back to stock.... Basically that I should get my truck reflashed and then put the programmer on. Should I return the programmer?