Alaskaworktruck

Newer cummins owner. I have been vastly educated by these forums. My question is about cats. I read in different threads that 03-04 had no cats while 04.5 + have a cat. I checked my door panel and I have a March of 04 production date and when I crawl under the truck I see what appears to be a cat. ( large device designed to disrupt exhaust flow) Are the statements that "there are no cats on 03-04" more of a general statement and that there are some 04's out there with one on it. I bought the truck new in Alaska and we don't have any harsh emmission laws. Any thoughts???

new2ctd

It's an 04.5 you have.
I think they started right there in March. So you got one of the first ones.

You can confirm by looking at the sticker on the left side of the valve cover.

rip 112

If you have a 305 hp rating on the side of the valve cover, its an 04. Otherwise it would be 04.5up, which you most likely have.

Dieselhed

My build date was March '04 as well. 600 motor. Came with a cat. Cat ran (fell) off.

Alaskaworktruck

O.K. you fellas are correct. The rated HP on the sticker is 325. I just assumed that the break between the 04 and the 04.5 was more toward the middle of the year and not in March. I guess that means I will have to change my sig!!! This will also slightly affect some of the planned mods I had in mind--hopefully for the better.