Acually if you are past warranty you have no worries. these chips will help longgevity on transmission for they remap the shift points and firm up weak shifts that will leghtn transmission life, see chips enhacements, As far as tampering with the PCM if you leave chip in yes may void warranty if its past warranty you have no fear! If you remove chip before like I stated in post earlier, if your dealer does a Diagnostic check with chip removed IT CAN NOT BE DETECTED DO TO YOUR PCM AUTOMATICALLY RETURNS TO DEFAULT SETTINGS. As far as Exhaust smog testing in most states diesel"s are exempt from testing. And in alot of states we dont need to run converters on diesel our Cumming and powerstrokes dont have converters. But some states do reqiure diesel converters. All gas motors have laws they must have converters on all cars over a certian years. I have been down to New England Dragway they have have there A Power Stroke making 1000hp and a Cummings with 1200hp all on redone race autos you ought to go see the Diesel truck shoot out at NH Dragway. Also see http://www.bluechipdiesel.com
they drag at New England Dragway to with some Cummings making big hp. Its hard to belive how easy the 94 and up Cummings can make so much hp with little modification.