So someone actually did it (KJ hemi swap)

04Liberty

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Found this little nugget on one of my Ram forums. Since you have to be a member to see it on that site:

Here is a different one for you guys. My brother has been working on this swap for awhile now and it is now finally up and running. It all started when we had a traded in 2005 Grand Cherokee that was a US vehicle and needed far to much to pass a federal inspection, so he picked it up for next to nothing.
He has had the Liberty for some time now and has lockers front and back with the lift and many other modifications for going off road. He asked me about what might need to be done to the powertrain to get the swap going so I got the VIN to see what he had for powertrain and that is when I discovered it came with a 3.7l engine bolted to a 45rfe trans... yep, just bolt it right to it.
Fast forward and the engine is stuffed in there and I gave him my old 2500 stall for the 45rfe trans. He had sent the cluster and harness to Hotwire and they tied it all together running off of a 2005 truck pcm with all the usual stuff deleted (egr, downstream O2's, knock sensors) and it fires right up.
He is just finishing up a couple loose ends like the electric cooling fan and exhaust but should be driving it within the next couple weeks. I can honestly say I have never heard of a Hemi powered Liberty so I give him extra marks for originality.

As you can see, it's an 05 LX 5.7 (only car version that had those coils) and it's so tight in there I doubt you can do much beyond plug changes without lifting the body lol.....but there it is. With the custom tune that is in there to run it, even with no other changes it's probably running 350hp or so at the crank (stock is 340hp with 390ft/lbs). That's 100ft/lbs more than a stock CRD. I dunno if he threw a cam in it or not, I'm waiting to see if there are more details.

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tommudd

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LOL, Not the first, was done many years ago.
Off road shop out west did one , only thing they also did a full width SFA and did it right since they knew the stock front (specially) diff would not hold up long with hammering the skinny pedal
Not much else about it since they pretty much kept it low key at the time
Troy had seen it when it was done due to him thinking of doing his, one of the reasons he went full width SFA
 
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04Liberty

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LOL, Not the first, was done many years ago.
Off road shop out west did one , only thing they also did a full width SFA and did it right since they knew the stock front (specially) diff would not hold up long with hammering the skinny pedal
Not much else about it since they pretty much kept it low key at the time
Troy had seen it when it was done due to him thinking of doing his, one of the reasons he went full width SFA
Never saw it, must have been before my time lol (and I've been here a minute).

Nice work. Congrats !
Not mine lol
I damn sure wouldn't wanna have to work on it/maintain it for sure...
 

Rob Williams

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Found this little nugget on one of my Ram forums. Since you have to be a member to see it on that site:

Here is a different one for you guys. My brother has been working on this swap for awhile now and it is now finally up and running. It all started when we had a traded in 2005 Grand Cherokee that was a US vehicle and needed far to much to pass a federal inspection, so he picked it up for next to nothing.
He has had the Liberty for some time now and has lockers front and back with the lift and many other modifications for going off road. He asked me about what might need to be done to the powertrain to get the swap going so I got the VIN to see what he had for powertrain and that is when I discovered it came with a 3.7l engine bolted to a 45rfe trans... yep, just bolt it right to it.
Fast forward and the engine is stuffed in there and I gave him my old 2500 stall for the 45rfe trans. He had sent the cluster and harness to Hotwire and they tied it all together running off of a 2005 truck pcm with all the usual stuff deleted (egr, downstream O2's, knock sensors) and it fires right up.
He is just finishing up a couple loose ends like the electric cooling fan and exhaust but should be driving it within the next couple weeks. I can honestly say I have never heard of a Hemi powered Liberty so I give him extra marks for originality.

As you can see, it's an 05 LX 5.7 (only car version that had those coils) and it's so tight in there I doubt you can do much beyond plug changes without lifting the body lol.....but there it is. With the custom tune that is in there to run it, even with no other changes it's probably running 350hp or so at the crank (stock is 340hp with 390ft/lbs). That's 100ft/lbs more than a stock CRD. I dunno if he threw a cam in it or not, I'm waiting to see if there are more details.

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Found this little nugget on one of my Ram forums. Since you have to be a member to see it on that site:

Here is a different one for you guys. My brother has been working on this swap for awhile now and it is now finally up and running. It all started when we had a traded in 2005 Grand Cherokee that was a US vehicle and needed far to much to pass a federal inspection, so he picked it up for next to nothing.
He has had the Liberty for some time now and has lockers front and back with the lift and many other modifications for going off road. He asked me about what might need to be done to the powertrain to get the swap going so I got the VIN to see what he had for powertrain and that is when I discovered it came with a 3.7l engine bolted to a 45rfe trans... yep, just bolt it right to it.
Fast forward and the engine is stuffed in there and I gave him my old 2500 stall for the 45rfe trans. He had sent the cluster and harness to Hotwire and they tied it all together running off of a 2005 truck pcm with all the usual stuff deleted (egr, downstream O2's, knock sensors) and it fires right up.
He is just finishing up a couple loose ends like the electric cooling fan and exhaust but should be driving it within the next couple weeks. I can honestly say I have never heard of a Hemi powered Liberty so I give him extra marks for originality.

As you can see, it's an 05 LX 5.7 (only car version that had those coils) and it's so tight in there I doubt you can do much beyond plug changes without lifting the body lol.....but there it is. With the custom tune that is in there to run it, even with no other changes it's probably running 350hp or so at the crank (stock is 340hp with 390ft/lbs). That's 100ft/lbs more than a stock CRD. I dunno if he threw a cam in it or not, I'm waiting to see if there are more details.

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I have an 02 Liberty Sport 3.7l. Absolutely mint condition and am considering a 345ci/5.7l install - new, carb'd. BTW the 02 was the first year and sat about 2" higher than subsequent years. Anyhow, are you saying the hemi will bolt right up to the existing trans? Do you have any more details?
 

tommudd

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I have an 02 Liberty Sport 3.7l. Absolutely mint condition and am considering a 345ci/5.7l install - new, carb'd. BTW the 02 was the first year and sat about 2" higher than subsequent years. Anyhow, are you saying the hemi will bolt right up to the existing trans? Do you have any more details?
LOL, the 02 was NOT 2 inches higher , it was actually 3/4 of an inch higher due to different springs which means nothing after 50-60,000 miles
To do it right SFA, ( then different trans, transfer case,new rear diff, may as well with the new front diff if you want to do it and make it last )
 

Rob Williams

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LOL, the 02 was NOT 2 inches higher , it was actually 3/4 of an inch higher due to different springs which means nothing after 50-60,000 miles
To do it right SFA, ( then different trans, transfer case,new rear diff, may as well with the new front diff if you want to do it and make it last )
Why do you say lol ? Be polite!! Specs say 02 Sport 4w is 73.2" high and 03 etc. are 70.2. I was told by Chrysler service years ago there is quite a difference.
What does SFA mean?
Maybe I misunderstand but I thought you said the hemi bolted right up to the existing 3.7 trans. I do not care about front wheel drive meaning transfer and front diff. This vehicle is strictly highway, on-road, and I'm looking for performance. I realize I would probably have to change the rear gears. BTW, I just had trans overhauled due to issues and the auto trans specialty shop told me 02 was the only year for my trans and that it was better than following years. As a result of being 1 off, you cannot find rebuilt 02's. Give rebuilders the ****** and they will rebuild it as I found out.
 

tommudd

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OH MY, polite ? I am being polite
everyone knows full well 02s were only 3/4 of an inch higher ,
Been around these KJs for over 18 years, building, lifting, doing everything one end to the other. Have owned 02s , have worked on them when they were still new .
Have several great friends who worked in the plant building them.
And they were NOT 2-3 inches taller LOL just ask anyone who actually knows , post up a POLL on here, you;ll find out
SFA - Solid Front Axle
And there's more than just bolting it in, wiring, cooling are just two starting points
 

Rob Williams

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OH MY, polite ? I am being polite
everyone knows full well 02s were only 3/4 of an inch higher ,
Been around these KJs for over 18 years, building, lifting, doing everything one end to the other. Have owned 02s , have worked on them when they were still new .
Have several great friends who worked in the plant building them.
And they were NOT 2-3 inches taller LOL just ask anyone who actually knows , post up a POLL on here, you;ll find out
SFA - Solid Front Axle
And there's more than just bolting it in, wiring, cooling are just two starting points
Lol is a critical response. You ignore what I mentioned about the specs showing 02 is 2-3 inches taller. This is shown on Edmunds https://www.edmunds.com/jeep/liberty/2002/features-specs/ Opinions don't make something a fact.
I realize there is more to a swap than just bolting in the engine but the most immediate issue is a trans to engine match. You said it bolts up. The rest is solvable as you said your brohter had done and got the motor running.
OH MY, polite ? I am being polite
everyone knows full well 02s were only 3/4 of an inch higher ,
Been around these KJs for over 18 years, building, lifting, doing everything one end to the other. Have owned 02s , have worked on them when they were still new .
Have several great friends who worked in the plant building them.
And they were NOT 2-3 inches taller LOL just ask anyone who actually knows , post up a POLL on here, you;ll find out
SFA - Solid Front Axle
And there's more than just bolting it in, wiring, cooling are just two starting points
Got cut off. Opinions and talk are not facts. I only mentioned the height diff because you said your brother raised his. I don't care but as I said specs show you are not correct. So LOL to you.
Edmunds says 02 is 73.2" and 03 plus are 70.2 - 71.1". You can find the same on other sites although there are some minor variances. Even so, 02 is 2+" higher and this confirms what Chrysler mentioned to me verbally. I have a friend who has an 07 Sport 3.7 and you can see the difference to mine by eye. See this https://www.edmunds.com/jeep/liberty/2002/features-specs/ and https://www.edmunds.com/jeep/liberty/2003/features-specs/ and https://www.edmunds.com/jeep/liberty/2004/features-specs/ .
I realize there are other issues in swapping out but the main concern is an engine to trans match. You said the hemi and 3.7 trans will bolt up. The rest such as electrical harness (available after market), cooling, etc is not a big deal and you said your brother got it figured out. Changing a trans is a big deal and would probably also involve modifying the length of the rear driveshaft whihc is very expensive. So, based on your remarks, the bolt pattern for a 3.7 to a 5.7l/345ci is identical and that's what concerns me.
 

tommudd

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BEFORE April 12, 2002 , hub to bottom of flare in front was 19.75 THAT IS FACT
After that date they are 19 inches FACT again
Whoever mentioned it to you was full of it for sure
False information you are showing
I've done full suspension replacement on every year of KJ there is , I've measured and remeasured and like I stated have many friends who built the KJs in Toledo ( where I lived for over 10 years, and all confirm the 3/4 inch difference
FACT NOT OPINION
DONE !
 

tommudd

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I never said my brother raised his, I do not have a brother as a matter of fact
Never said the transmission bolted up either
Now if comparing April 10, 2002 ( before the April 12, 2002 change in suspension ) Renegade against an 07 the Renegades BODY would be taller of course due to the renegade Roofrack , not body
Plus I have had many KJs come in my shop an inch to inch and a half lower than new stock since the OE suspension is very weak. Front springs rated at 310 LBs where they should of been 340-345 LBs

Measure left front on level ground, middle of hub to bottom of the flare and report back
 

Rob Williams

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I never said my brother raised his, I do not have a brother as a matter of fact
Never said the transmission bolted up either
Now if comparing April 10, 2002 ( before the April 12, 2002 change in suspension ) Renegade against an 07 the Renegades BODY would be taller of course due to the renegade Roofrack , not body
Plus I have had many KJs come in my shop an inch to inch and a half lower than new stock since the OE suspension is very weak. Front springs rated at 310 LBs where they should of been 340-345 LBs

Measure left front on level ground, middle of hub to bottom of the flare and report back
Sorry. Now I realize my reply was to 04Liberty at the top of this site and I see you jumped in after I did a reply to his posting. I don't have a Renegade and never said I did. 02 Liberty Sport. Edmunds is reliable.
 

tommudd

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So are the folks that built your Liberty
and so am I
NEVER said you owned a renegade , was stating that body height of a KJ renegade is taller which maybe where Edmunds is getting their measurements
 

04Liberty

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Lol is a critical response.
Only if you have paper thin skin....
I have an 02 Liberty Sport 3.7l. Absolutely mint condition and am considering a 345ci/5.7l install - new, carb'd. BTW the 02 was the first year and sat about 2" higher than subsequent years. Anyhow, are you saying the hemi will bolt right up to the existing trans? Do you have any more details?
I didn't say shlt LOL. All I did was post pictures and a blurb from something I found that was KJ related. However what I will say is:
1. Don't come brand new into a forum and immediately get butthurt.
2. Grow a thicker skin.
3. Yes, the 3.7/4.7/5.7 use the same bolt pattern; any random idiot with even slightly familiar with Jeeps and trucks these years should know this because they all have a transmission in common.
4. I'll probably get b!tched at for this, but you are an absolute IDIOT if you want to carb that engine within a modern electronic vehicle that you yourself said was strictly on road. Say you decide to use the RFE; the PCM you're gonna need to control the trans (unless you're going manual) is gonna tell you to get bent because it has no inputs from the engine. Not only that, were you planning a completely custom gauge package independent of the bus? Because without the PCM you have no gauge inputs. If this were a stripped down strictly off roader it would be a different story.
Have fun with all of that BWAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA
 

Rob Williams

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Only if you have paper thin skin....

I didn't say shlt LOL. All I did was post pictures and a blurb from something I found that was KJ related. However what I will say is:
1. Don't come brand new into a forum and immediately get butthurt.
2. Grow a thicker skin.
3. Yes, the 3.7/4.7/5.7 use the same bolt pattern; any random idiot with even slightly familiar with Jeeps and trucks these years should know this because they all have a transmission in common.
4. I'll probably get b!tched at for this, but you are an absolute IDIOT if you want to carb that engine within a modern electronic vehicle that you yourself said was strictly on road. Say you decide to use the RFE; the PCM you're gonna need to control the trans (unless you're going manual) is gonna tell you to get bent because it has no inputs from the engine. Not only that, were you planning a completely custom gauge package independent of the bus? Because without the PCM you have no gauge inputs. If this were a stripped down strictly off roader it would be a different story.
Have fun with all of that BWAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA
Only if you have paper thin skin....

I didn't say shlt LOL. All I did was post pictures and a blurb from something I found that was KJ related. However what I will say is:
1. Don't come brand new into a forum and immediately get butthurt.
2. Grow a thicker skin.
3. Yes, the 3.7/4.7/5.7 use the same bolt pattern; any random idiot with even slightly familiar with Jeeps and trucks these years should know this because they all have a transmission in common.
4. I'll probably get b!tched at for this, but you are an absolute IDIOT if you want to carb that engine within a modern electronic vehicle that you yourself said was strictly on road. Say you decide to use the RFE; the PCM you're gonna need to control the trans (unless you're going manual) is gonna tell you to get bent because it has no inputs from the engine. Not only that, were you planning a completely custom gauge package independent of the bus? Because without the PCM you have no gauge inputs. If this were a stripped down strictly off roader it would be a different story.
Have fun with all of that BWAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA
Boy, ask a short question and make an aside comment about height and you guys treat people like shxx. I don't need thicker skin - you both have no manners and treat people badly. I didn't know the trans were the same bolt pattern and that's why I asked a simple question to confirm so why call me an idiot? Seems to me that you posting a blurb is the same as saying it yourself because you obviously endorse the content.
The opposite of what you say about EFI vs carb from everything I have read is that swapping in a hemi and trying to use existing EFI is a huge and costly problem. All the parts for a carb install are available as are the electronics, even precalibrated for a stock or performance cam. There are numerous carb manifolds available from a number of aftermarket companies see https://www.motortrend.com/how-to/horsepower-with-carbureted-modern-hemi/ and https://www.shophemi.com/m-3-mopar-performance.aspx There is more from other sites if you look like https://www.manciniracing.com/inmahaandga.html . The base 5.7 hemi will deliver 376hp on the OEM base cam with 4v carb vs 345hp on EFI. Adding a cam gives 420-438hp on a carb according to Motor Trend. All these numbers can vary somewhat from one article to another but a carb version always delivers more hp than EFI, is an easier install according to these people and has more potential. If you order crate hemis from MOPAR and if there is a carb version selection available like the 392 and 426, it offers more hp. Turbos are also easier to install and calibrate on a carb engine - just saying.
 

JRB

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I'm newer to this forum, and liberties myself. This is a liberty forum, where a lot of people enjoy working on their own stuff and have learned some things over the years, and share their experiences and advice.

The height one is easy to see if you or tom are right, take pictures of the measurement of the center of your hubs to the top of the wheel well/fender area and see what the #'s show. I don't know tom or agree with every single thing he says, but if I were betting, his numbers are going to be much closer. Why? The limits of the geometry of the IFS. If yours is different, it would be cool to see and learn what they did different, maybe someone put stiffer suspension on it.
 

JRB

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Agree with Tom ???? LOL
But yes the figures I post are right on
Lol, to clarify I agree with all the help you give. It helped a ton when I joined and needed a lot of info on the front end of my liberty (and anyone else who gave advice)
 
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