Differences between 03 and 04?????

94f450sd

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Ok so my first dive into these piles of crap was going ok till I put both motors side by side to swap stuff.


The original motor is an 03.the replacement is an 04.

Before I got too deep I found the 04 motor has a sensor in the passengers valve cover,the 03 diesnt.so I pop covers off and everything is completely different with what I guess are the hpo rails.

Turbo mounting is different.egr cooler is different.

Sooooooo what do I gotta do to put the 04 motor into the 03 truck????
 

Thewespaul

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@Crawler would know more of the details, but first thing that comes to mind for me is the tuning differences between the years, iirc the 03 doesn’t require a delete for tuning but the 04 does, so you may run into computer issues because they are programmed different.
 

94f450sd

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This is the stuff that makes me wanna get out of this business. There was no need to change so much **** in a year.and if they're gonna change it,make it so it fits the older ****.freek8n rediculous!!!
 

Thewespaul

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This is the stuff that makes me wanna get out of this business. There was no need to change so much **** in a year.and if they're gonna change it,make it so it fits the older ****.freek8n rediculous!!!
It’s why I did, now I really only wrench on IDIs. They got their own pesky things, but much more easier to work around than these newer diesels.
 

Crawler

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2003-2004(early) are one version.
2004.5-2007 are another version.

2003-2006(early) use 18mm dowels to locate the head to the block.

2006.5-2007 use 20mm dowels.

20mm dowel heads can be used on 18mm blocks with 20-18mm stepped dowels. And some other stuff.

As frustrated as you are. The setup you bought (04.5-07) is a better setup.

The ICP sensor is in a better location, the HPOP is typically more durable, and more.

You have a couple choices. Switch everything over and get an 04.5-07 wiring harness or keep your 03-04 stuff and put it on the 04.5 engine.

If it’s in the budget, I would get an 04.5-07 wiring harness and use the newer parts.

What is the story on the truck? Meaning why do you have a second engine? I don’t know any background on your situation. Sorry. Once I do I can help determine what you should or shouldn’t switch over.
 

Crawler

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And now that I think about it, 04.5 was even more weird. Some had the 03-04 HPOP with a different cover and the icp, rail, and standpipes like an 05.

Their were a few odd balls.
 

79jasper

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I would like to know "why" as well. Could be wasting time swapping.
Personally I would stick with the 03 rails.
But there's no reason you cant drop it in the way it is, minus swapping the harness.
But if leaving the 04 stuff, better do the stc, dummy plugs, and stand pipes.

Sent from my SM-N960U using Tapatalk
 

Crawler

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I believe you could use your harness. Just remove the icp from its location in the harness and extend the wiring to reach the passenger valve cover. I have done them with new harnesses because most of the time the 03 harness has already been molested a bunch or has a few chafed spots. So rather than patch it up, the customer is given the option. If you’re doing the work yourself, you may consider just splicing the wires and extending.

You will want to use an 03 icp sensor in the new location. The 03 icp is a different voltage than an 04.5 up icp sensor.


The newer sensor works. But the computer will see a slightly higher pressure than what’s really there. It’s usually not a problem. However it can cause issues on some trucks.

The 03 icp has a KOEO voltage of .18-.19 volts. The 04.5-07 sensor is .24v
 

94f450sd

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After some extensive googling.supposedly all I need is the harness to the 04 motor,of course junkyard cut it.

But in the case of not having the harness.i need to extend the icpc wires to reach the head sensor or use the 03 sensor in the 03 location.i opted for the 03 setup,let the dead icp in the head go for the ride.


Motors back in it.bolting it all back together now.
 

Crawler

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Agreed on the stc, dummy plugs, and stand pipes. I keep a whole set of that stuff in my inventory at all times.
 

Crawler

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While you have it apart, I would swap sensors and move it. It’s just a little work. But it’s not any more work than replacing an 03 icp sensor and pigtail down the road if you have a failure.

Be sure to check your icp KOEO before you button everything up.

They are a pain to do with everything bolted up if you keep the 03 location.





For future reference the best way to get to the 03 icp sensor with all parts on the truck, is to reach up from the bottom (my hands are too big to do it from above) Snake your arm up past the bellhousing and you can unhook the plug.

Swapping the sensor from above is easier if you have the offset tool for it.

Otherwise you can use a fan belt wrench and do it from below as well.
 

SebastIDIan

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I believe 03-04 had a "throttle body" or valve in the intake elbow iirc. Not sure if it's relevant or not.
 

94f450sd

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I believe 03-04 had a "throttle body" or valve in the intake elbow iirc. Not sure if it's relevant or not.


03-04 did.04.5-up didnt.doesnt need it.they changed intake,up pipe, egr cooler in 04.5,turbo mounting,


But supposedly everything will work.we will see tomorrow when I fire it up.
 

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