How to improve towing for 2007 Chevy 2500 HD Duramax

^ this. Even most guys who tune realize it is a can of $$$. Tune leads to increased egts, needing monitor gauges. Also fuel starvation needing lift pump, higher flow injectors etc. If you want a drag truck build one. For towing any well maintained recent stock diesel is more than enough. My stock lmm has more power than I'll ever use and that's pulling 12000 lbs. not even mentioning the legality parts which is another level of pain.