hi i am new to the diesle community. i just got my first duramax 2003 it has a 5" turbo back exhaust. and i believe thats the only mods it has and ever had. but i was wondering what your guys suggestions would be on doing to get the most out of my truck. ive never been to the track or anything but love speed and power. but also like money in my pocket so anything to boost my mpg would be awsome.