Alright I just bought another 2004 Ram 3500 and I was told it was a early 2004. The truck has the APPS but it also has a 351 turbo that is plugged into the wire harness, did they have the newer turbo with the APPS for a short period of time during the changeover? My engine is missing the plastic cover with the engine info on it so I am a little confused. Is there any other way to tell the difference?

 

If it was built after 12/31/03, then it should be a 04.5... Before that date should be a 04..

 

Who knows what engine is in your 11 year old truck. It could be a 2003 SO or a 2007 5.9L or anything in-between and any infinite combo of parts.

As for your truck, as was stated, Jan 1, 2004 was the cutover point for the 2004.5 trucks. This is the Chrysler manufacturered date found on the door jam.

1 of the visual changes that is pretty reliable is that the coolant overflow tank is on the passenger side firewall on the 2004.5 trucks.
It's on the driver's side by the radiator on the earlier trucks.
The overflow tank can be swapped but I doubt many would do that.

 

Oh yah, on the 04.5 trucks that radiator shroud was connected to the engine or something like that... the radiator shrouds are different if you google some pictures...

 

The data plate on the engine will show you the horsepower. An 04.5 should show 325 HP. An earlier one will either show 250 or 305 HP.