I'm getting ready to purchase an '04 2500. How do I know if it's an 04 or 04.5? What are the differences between the two?

Rob

 

There is a sticker on the driver's side of the valve cover. It will give the rated horsepower @ 2900 rpm. If it's 305, it's an 04. If it's 325, it's an 04.5 The '04 will have 305 hp and 555 torque stock, 3.5" exhaust, and no catalytic convertor. The 04.5 will have 325 hp and 600 tq, 4" exhaust, and a catalytic convertor. Just like a gasser, it's against the law to remove it.

 

Look at the sticker on the driver's side of the valve cover.....it will say either "ISB 305" or "ISB 325".

Greg

 

If you pop the hood and look on the driver's side valve cover you will see a whit sticker. Look at the advertised HP. It will say 305 or 325. If it says 325 you have an 04.5. Also, the manufacture date for the 04.5 will be 01/04 or later.

The difference is the HP and torque. The 04.5 has 325 HP 600 TQ and the 04 has 305 HP and 555 TQ. Not much else is different. The 04.5 will have a catalytic convertor and the 04 won't unless it is a CA model. The 04.5's have a 3 rd injection event which aids in cold startup (white smoke, rough idle) and also to keep the catalyst in the CAT hot enough to burn the gasses.

FWIW it seems the 555's get better mileage.

 

Any other tips or hints about the '04's / 04.5?

Rob

 

One more thing, the 04.5 is electronic wastegate and the 04 isn't.