6.4 Hemi Trucks

My 03 2500 desiel gets 19-20 around town and 24.6 on the highway. Towing car on open trailer was 16. Best thing I did was the full 4" exhaust from the turbo back. Did the hypertec down load stage 3, fun as hell but ate to much fuel. Went back to the stage 1. Last truck I'll ever buy, should last me till I cant drive anymore.