RayNAz

Thanks for all the advice. Looking at the Quadzilla tuning threads it looks complicated enough without having to account for an already tuned ECM. My understanding is that the Smarty programmers come with a library of "stock" programs by VIN so I may go that route depending on how much the dealer wants to do the flash. l can probably sell the Smarty if I feel that I need the extra features of the Quadzilla. Maybe I'll get lucky and find a used smarty locally.

Am I correct in assuming that if I want to use a piggy back style tuner such as Quadzilla that I would first need to find someone to re-flash my ECM to stock? Is that something that most shops would be able to handle?

About 2 years ago I bought a 1999 2500 with a 5.9L 24v Cummins. The PO claimed that he "had a tune put on it" but couldn't be more specific. It definitely makes more power and smoke than the similar stock trucks I've driven and there's no sign of any piggyback tuners on the truck so presumably he used a Smarty tuner or similar. The only other mod that I know of is the Airdog Raptor lift pump that I installed but with a little over 200k who knows what injectors are in it etc. I mostly use this truck as a road trip vehicle both for work and camping and it usually has a small (1800lb) pop-up truck camper on the back. This is a mountainous area with lots of long steep grades. I'd like to be able to adjust the tune in order to get rid of some of the smoke and hopefully gain a little fuel economy. Having the ability to switch between mpg/power tunes would be great but once I get my tune(s) the way I like I don't plan on messing with it much. Reliability is more important to me than max power. Adding a piggyback style tuner on top of a tuned ECM sounds like trouble so I'm considering a Smarty or similar. I suppose if necessary I could find someone to flash it back to stock and then buy a piggy back style tuner. I'd prefer to keep my ODB port available since I frequently use it with an app to monitor mpg etc while driving. Any suggestions?