i have just currently bought my 3rd lly duramax. i seem to dump a whole lot of money in them and sell them. i dont know why call me crazy i guess. i recently picked up an 04 1/2 with 140k miles on it. not looking to add a whole lot just mainly add to fuel milage since its my daily driver. truck is all stock now besides cold air intake and after market rims. waiting on MBRP exhaust to come in. down pipe back no muffler no cat. if anyone has suggestions on how to get the best fuel milage im open