So someone actually did it (KJ hemi swap)

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Even though the transmission for a 3.7 will bolt up to a 5.7 hemi, can it handle the extra power
 

04Liberty

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Even though the transmission for a 3.7 will bolt up to a 5.7 hemi, can it handle the extra power
If it's the 45RFE yes. If it's the 42RLE no. The manuals I'm not sure about, but most likely not. Depending on whether it comes out of a pre-eagle car or truck, that's 375 to 390 lb-ft on the stock cam.
 

James Akemon

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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.
That was Tom being polite.
 

Flyboyjonesy

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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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If this is possible does that mean a Stellantis Hurricane 3.0 L I-6 could fit in a Liberty? How accesible is the oil filter? Does anyone have the dimensions of the stock 3.7L PowerTech and the engine bay of the Liberty? The Hurricane dimensions are L 33.4in, W 28.7in, 32.7in.
 

04Liberty

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These are really silly questions to ask me as 1) I have never seen a new I6 in person and 2) no one so far as I know has attempted to put one in a KJ. The problem you would have here is trying to integrate the much later generation CAN PCM into your much older PCI bus vehicle. This would require a standalone controller that is actually capable of running it properly (which may or may not currently exist). I know a Holley will run a modern VVT hemi and integrate into a PCI bus Ram, so it is theoretically possible but I don't know if it can run a Hurricane.
 

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