hey...im new to the site and i just bought my first cummins and i was jsut wondering how to tell if its an 04 or an 04.5 and was wondering what the difference is in the two. i just bought a procomp 5 inch lift and 37'' all terrains im going to put that in next month on my time off, i was wondering if anyone is running this lift and was wanting to kno what troubles i might run in to during the install with it... i was also wondering about a chip i was wanting somthing nice and reliable ive been thinking about getting a bully dog triple dog but i was wanting to kno waht the tst is and someother ones thanks for any help, matt

 

Pop the hood and look at the drivers side valve cover. It should have the HP rating on it. A 555 will be 305HP and the 600 will be 325HP. Or you can crawl under it see if you have a cat. Also the 555 had a mechanical turbo where the 600 has an electric wastegate.

 

When you look on the valve cover 305/555 will be a 2004, 325/600 will be a 2004.5.

 

thnaks for the help guys im gonan go check it out right now

 

alright my motor says advertised hp 325 and i have a cat...i looked at my moms 03 and it says advertised hp 250, shouldnt hers be a 305 or is it because the build date on the motor says 12/05/2002

 

Must be a California 2003 engine model. Pretty sure in 2003 there were special versions to meet California emissions regulations before they could be sold in that State.

 

would that 325 and the cat make my truck a 04.5 model then? if so i was thinking about a tripledog powerpup chip i priced one out today thanks for the help guys..best site ive found so far

 

Yes you have an 04.5 model truck. Your moms is an 03 standard output. When the 600s came out they were 50 state compliant so one motor fits all. There is still an emmissions sticker for Cali and a few other states. The motors are identical. Each one needed to my smogged at the factory instead of every so many for the rest of the states. Hope that makes sence.

 

California engines in 2003 were 235HP due to the CAT. The 250HP was a standard output engine without a CAT, and was standard in the other 49 states until January 2004 when the 305HP was introduced. The 250HP remained an option through the rest of the 2003 model year.