Q Difference between 04 and 4.5

[JacksonH]

I have a 2004 2500 4x4 Qcab longbed Whats a 4. 5 ?? compared to an 04. Any difference, or not related at all. ?

 

[Buddy's Ram]

The 04 has 305 HP and 555 Ft Lbs torque, and no Catalytic converter. The 2004. 5 has a converter, 325 HP and 600 Ft Lbs of torque. I think this is the major difference. Someone correct me if I am mistaken.

 

[R_Painter]

plus on a 04. 5 the turbo has aelectronic wastegate and most aftermarket performance programmers that work on 03-04 will not work on 04. 5 and 05 trucks.

 

[jjdiesel]

The most talked about difference is the third injection event on the 04. 5 and the adverse affect it has on mileage, at least on many of the trucks. It also has a cat, and iconel valve seats... . better

 

[Pawpaw]

Any trucks built after Jan 1, 2004 is an "04. 5". As others have stated, the 3rd injection event and catalytic converter are two big differences.



A straight 04 could be had in 3 different power ratings. I think the SO was 250 HP, the HO was 305 HP. There was also a California emissions model which I think was 235 HP.



Look under the hood at the sticker on the driver's side of the valve cover cover (it's plastic). As an example, mine says "ISB 305".



If the sticker is missing, look at the radiator fan shroud. If it's attached to the radiator, it's an 04. 0. If it's attached to the engine in any way, it's an 04. 5.



Bob

 

[SDunkle600]

Also, the injectors are slightly different on the 04. 5 and up. I believe it has more holes and different spray angle.

 

[BrianJ]

'04. 5 has a bigger turbo, different heads/injectors, different programming (i. e. 3rd injection event), cat, and bigger exhaust (4" front to back vs 3. 5" from turbo to muffler on the '04), which all equal 325/600 vs 305/555 for HP/TQ compared to '04 HO.



As for mileage comments, I have seen both get over 20 and I have seen both get only in the mid teens (empty). It really is a crap shoot with both versions and determined by many factors.