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04 or 04.5 motor?

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305 or 325 04 dodge??????

According to vin ,build date ,and tag on valve cover its supposed to be a 325 04.5 dodge cummins.

Just pulled my injectors to have them tested and they say they are 305 injectors. Their basically all junk so I need to get new ones. So its its 325 motor or a 305? Don't know what else is different about these motors to know for sure what I have.

Any Insights would be appreciated
 
The 04.5 has an engine mounted fan ring with a boot. I'm pretty sure the 03 has a traditional one piece shroud. The 04.5 has a cast elbow on the turbo to remove for a exhaust brake. I don't think the 03 has that either.
I know one member here that can run your engine serial #. If he chooses to jump in.
 
Yeah what im wonderin now is if someone threw in wrong injectors or replaced motor with a 305 and put original valve cover plastic with 325 horse serial and cpl info
 
The 04.5 has an engine mounted fan ring with a boot. I'm pretty sure the 03 has a traditional one piece shroud. The 04.5 has a cast elbow on the turbo to remove for a exhaust brake. I don't think the 03 has that either.
I know one member here that can run your engine serial #. If he chooses to jump in.

The 03 had a cast elbow and two piece fan shroud and I believe the engine mounted fan came in 06 but could be wrong on that one.
The ID plate on the side of the timing cover tells what it really is.
 
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It's my understanding that this is a 03-04 fan shroud.
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This is is what my 04.5 shroud looks like. It's like a class 8 truck style where it has struts coming off the engine holding a ring and a flexible boot connects to the rad mounted shroud.
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Its also my my understanding that they installed the cast elbow at the turbo to accommodate a brake since the .5 had a 48RE brake capable trans. I don't know what a '04 down head pipe looks like.
I believe this is a valid visual way to seperate a 04.5/ 600 engine from the earlier 3gen engines.

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Its also my my understanding that they installed the cast elbow at the turbo to accommodate a brake since the .5 had a 48RE brake capable trans. I don't know what a '04 down head pipe looks like.
I believe this is a valid visual way to seperate a 04.5/ 600 engine from the earlier 3gen engines.


The 04.5 Auto trans was not exhaust brake capable - at least not per Dodge. That came in 2006.
The 2003 (which I have had since new) had the cast elbow so an exhaust brake could be added to the Manual trans trucks - which I did.
The 03`04 engines had a two piece fan shroud as well (Upper & lower) but it didn't hang off the eng like the 325 HP eng did.

Cheers,
Scott
 
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I Apologize for 2 piece confusion. The .5 shroud is not split, but in sections. The radiator portion and fan come out together. At least that's how I did my visit tonic clutch.
I thought the 48 RE was brake approved. The 03-04 had a 47 trans- is my memory fading?
 
I Apologize for 2 piece confusion. The .5 shroud is not split, but in sections. The radiator portion and fan come out together. At least that's how I did my visit tonic clutch.
I thought the 48 RE was brake approved. The 03-04 had a 47 trans- is my memory fading?

Nah, when they finally built up the auto enough to go behind the CR third gen "HO" engine in 2003, it was a 48 but they drug their feet getting it ready for the E brake. (You could get a CR engine with the auto in late 02 but it had to be the 250 HP version and still used the 47.)
Finally in 2006 they beefed up the ECM and improved a thrust washer inside the 48RE and finally blessed it for an exhaust brake.
Lots of people did it before then though!
 
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The Turbo exhaust will be 4" to the 4"down pipe for the 04.5. But if you pulled 305 injectors, research the engine block number.
 
All outward appearances it's should be a 325. Piston cups are different between the two and injectors spray different angles and different amount of holes.
 
It is not unusual to see the 143 pattern injectors in a used 325 engine, they work just fine. With a used truck it is hard to tell what has been done, verify the version with a block number or look at the pistons.
 
Its extremely import NOT to mix injectors on OE trucks, Don't believe the BS that BMS sellers promote...the 2003-04 are 8 Hole 143" ,2004.5-07 5.9 5 hole 124"... 2 different piston bowls, entirely different OP systems... Yeah inter-changing works but its not OE or correct.

Modded engines race competition, you can inter-change when tunes are written correctly.
 
Pulled head. Motor was either rebuilt or a short block put in. It has 305 Pistons in it.
Serial # that was on valve cover was definitely for a 325. Waiting to hear from dealership to confirm vin says it was supposed to be a 325.
So 305 injectors it is. But does 325 programming firing 3 times vs 2 times for a normal 305 motor going to affect how it runs
 
Yes the running pressure in the 325 are much higher then the 305. You must mate your injectors to the OP system and piston style.
 
I bought this truck at auction because body was perfect from California. Not a spot of surface rust. Not even on cast elbow off turbo.
Figured I can do lots of mechanical for answer body. So I know nothing of motor. Other than had no blow by
 
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