This may not apply to your truck but I received a letter from Chrysler that the ECM warranty on my 2004.5 has been extended to lifetime coverage. The letter states that it only applies to 2004/2005 2500/3500 5.9 engines that are equipped with California emissions. It relates to state mandated inspections and not complete failure but the letter was dated 2010 and maybe failure is now an issue as well. If you have a very early 2006, maybe it has a 2005 ECM. Just for your information in case you find a connection to this issue and your problem.
That has to do with monitors not showing correctly for the smog test in Cali and does not apply to 06 my