Motor Swap // 4.7 to 5.7

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VictorBermea

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Texas
Ram Year
2003
Engine
5.9L Common Rail 24V Cummins TD
So, I've got a RAM 1500 with the 4.7L SOHC motor in it. I bent all the valves on the driver side because the timing went out while doing a cam swap. Well, now I need a new motor. I spent all day today pricing used and remanufactured motors. Found a 4.7 for a price you can't beat. So I began to think is it possible to put a 5.7 HEMI in my truck? I mean it's the same engine bay, same everything besides a motor. Since the reman 4.7 motor wasn't over priced I could probably get a HEMI from the same guy with a decent price as well. Since, I have to get a new motor anyway, why not put a HEMI in it? Go big or go home right? Haha. I just need to know if a HEMI would fit even though I had a 4.7 in it?
 

MegaMouseGW

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2007
Engine
SRT 10 Viper Motor and Tranny
Shoot yes a HEMI will fit. Heck my 07 has the V10 in it. But that was a tight fit. Dealership had to almost tae the entire front end apart to get it in there, but it was definitely worth it.
 
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VictorBermea

VictorBermea

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That's music to my ears. I want to drop a HEMI in my truck instead. Wouldn't make a difference, I need a new motor anyway. Haha. Thanks man.
 

Redtruck-VA

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2003 & 1989 D250 RWD
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Hemi-5.7, 5.9 12v & 24v diesel
I haven't done this, but have read where others have. It seems to be a common swap and I thinks there are some advantages as the 4.7 PCM uses a drive by cable TB. You could use your 4.7 PCM and a LSX TB with a adaptor. I would check with some different tuners to see who has tuned this conversion and see if they have any recommendation. The engine fits fine the problems will be working the tune out properly. Worst case I suppose would be to swap to a 5.7 PCM, but that also has it's challenges. Good luck...
 

EWC88

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Southern NJ
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2002
Engine
4.7
I thought I read somewhere that putting a hemi to the tranny on a 4.7 is bad, could be fully wrong, but I'd like to know this answer too!
 

MegaMouseGW

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There will be other things that have to be changed also. The radiator will have to be upgraded, possibly the tranny if it is not one of the ones that was used on both the 4.7 and the hemi. Expect to get new motor mounts and not sure but a few other things also have to be changed out. Not sure if there is a post here on what has to be done.
 

TexasRammer

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4.7
Its doable, and im not positive but I think 2005 is like the best year to do it on. I would search around to see what all you needed. When I was thinking about it I saw all kinds of info
 

ST-8

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5.7
Why wouldn't you think a hemi would fit??
 

emjohn4

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Hemi 5.7
I thought I read somewhere that putting a hemi to the tranny on a 4.7 is bad, could be fully wrong, but I'd like to know this answer too!

The same transmission is used for the 4.7 and 5.7.
 

emjohn4

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Hemi 5.7
You can do it, yes. Lots of WTF in this thread so far.

It's not plug and play with your 4.7 PCM. It would be best go get a wrecked 5.7 donor truck, so you can get all the mounts, wiring, and PCM from it.

It's a bit more complicated that just dropping the 5.7 in and plugging it into your current truck. You need all the associated wiring harnesses and PCM to support the 5.7.
 

Casper

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2020
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5.7L
You can do it, yes. Lots of WTF in this thread so far.

It's not plug and play with your 4.7 PCM. It would be best go get a wrecked 5.7 donor truck, so you can get all the mounts, wiring, and PCM from it.

It's a bit more complicated that just dropping the 5.7 in and plugging it into your current truck. You need all the associated wiring harnesses and PCM to support the 5.7.
Ditto. If you can be without your truck for a few weeks while you sort out PCM, tune, throttle body, wiring harness radiator and motor mounts etc., then you've got a project. Otherwise, your 4.7 is much closer to plug and play depending on year of mfgr--course you could do the cam and beef -up the lfters before you installed it.
 

Redtruck-VA

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This is done often by the Durango crowd. You might check their forums to see what they did. The 4.7 PCM being cable drive has advantage and there have been many conversions using the 4.7 PCM. If swapping PCM's I would say the 05 is definitely the one to use. Good luck...
 

Redtruck-VA

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I've lost touch with this swap. 07 concerns are the 58 tooth tone wheel. 03 to 05 have 32 tooth rings. 05 is by far the best pcm for tunability IMO. I've installed one in my 03 and it nicely supports my supercharger/cam combo.. need to talk with folks who have done the swap and learn from their experiencesite. Good luck.
 

chrisfischer79

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2012
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1500
I have a 2012 1500 with a 4.7. I see all the info for 3rd gen 4.7 hemi swaps but nothing on 4th gen. i found a donor truck a 2010 what all would i need to get from it and do to swap my motor to a hemi? Sorry if this isn't the right post but i'm new on here and it wont let me start a new thread
 

Amyt0410

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2003
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4.7
Will a 2004 4.7 magnum fit in a 03 ram?
 

Maurice

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2003
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5.7
What is all the associated wiring harnesses Consist of I have the wiring harness for the 5.7 hemi motor I just ordered the fuse Box and wiring harness for the 5.7 motor What else do I need I'm doing the same swap 2003 ram 4.7 swap to 5.7 hemi
 

Adamlw557

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Location
Salisbury
Ram Year
2011 and 2016
Engine
5.7 and 4.7
So, I've got a RAM 1500 with the 4.7L SOHC motor in it. I bent all the valves on the driver side because the timing went out while doing a cam swap. Well, now I need a new motor. I spent all day today pricing used and remanufactured motors. Found a 4.7 for a price you can't beat. So I began to think is it possible to put a 5.7 HEMI in my truck? I mean it's the same engine bay, same everything besides a motor. Since the reman 4.7 motor wasn't over priced I could probably get a HEMI from the same guy with a decent price as well. Since, I have to get a new motor anyway, why not put a HEMI in it? Go big or go home right? Haha. I just need to know if a HEMI would fit even though I had a 4.7 in it?
 

Adamlw557

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Salisbury
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2011 and 2016
Engine
5.7 and 4.7
Did you make it work in in the same boat tell me what you did
 
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