what build date separates the 2004 from the 2004.5 and what changes were made?

 

There are several posts listing the difference. As for the build dates,Somebody correct me if this is wrong.
I think 04 was built up until the end of 2003, everything built after Jan is a 04.5
I may be wrong on this (I am wrong a lot)

 

I think Ray Roton is correct on the dates. The 04.5 has the Cummins 600 engine which includes a 4 inch exhaust pipe thru-out. The cowling to direct air to the 600 is also different (attached to the engine). If there are other changes, I don't know about them. I have an 04 2500 555 and have an 04.5 600 due in soon. The dealer says that there are no differences other than what I've mentioned.

 

thanks for the info---les novikoff