Is the 2008 Cummins/Ram DPF re-gen fuel added post injection in the cylinder or is there a separate injector in the exhaust? I couldn't find any real info at cummins.com. I have a Cummins quickserve account but I can only access manuals for my '99 ISB. Hemi truck club pulled the plug on their FSM downloads and the newest one I have is 2006.