before you put any tuner on there, upgrade the transmission. get yourself some gauges (trans temp, boost, EGT, rail pressure), ditch the EGR and DPF if you can get away with it where you live, get a good lift pump (raptor airdog or fass 100GPH or higher) and then you might look into a smarty programmer (its the best for a common rail truck)
I'm not very experienced in common rail trucks, but I do know the smarty is top dog in the programmer field for your truck...check out cumminsforum.com and do some reading. that is by far the best and most informative site for anything you could ever possibly want to know about your truck. plenty of helpful guys and sponsors on there.