Alright fellas I have an 08 250 6.4 ecsb. Has xrt,5inch downpipe back,intake around 93k. I am having a major issue with the fuel mileage on my truck. About !15-16! on highway/here and there..! And that's not running it hard just normal. is what I get on the highway mixed with some other driving. I was getting. I was getting better with the dpf still on it!! I've heard of guys getting atleast a little over 20mpg... I have also threw the diesel clean to it also as I try to all the time. There is nothing wrong with the truck at all it's healthy as a horse and runs like a wicked 6.4 does. I have the proflo egr delete kit which I am installing this month. Even though the egr system is turned off could this be why my mileage is so bad? Which engine tune and trans tune should I run for safest best mileage with performance? If I can't see any better mileage out of this rig I am afraid I will start to think about replacing it with something else. Thanks a lot in advance.