you can also look on the valve cover. . .if the HP rateing is 325, then you have an 04.5, if it is a 305hp model then you have an early 04. also the build date of the truck will also tell you, after Jan 04 then you have the 600 engine, before that would be the tripple nickel.
4/28/07 392hp 716tq on the stock clutch
10/20/07 425hp 798 still on the stock clutch
BIG THANKS to David and the guy's at James O'neal Dodge.
YOU GUY'S ROC
That makes your an '04. The 04.5's have a build date on or after 1/1/2004
2004.5 Ram 2500, Cummins 600, 2WD, LWB, Bully Dog Triple Dog with Outlook, AEM CAI, 4" ANSA Silverline no cat exhaust, Oilguard system, 2nd lift pump CARPENTERS LOCAL 1506
BUILDING IT RIGHT THE FIRST TIME, EVERY TIME