OK, so let's be serious...4.7l swap.

[JeepCoMJ]

yup.

It isn't going anywhere, I'm leaving a deposit when this motor sells today. I'll pick it up when the black one sells, which gives me time to prep all of the other parts for a one-time install and mount then finish up the engine bay.

 

[Honduras]

Bought an '02 Grand Cherokee 4.7l HO. Completely rebuilt brand new, comes with full gasket kit and install kit (hoses, plugs, distributor, water pump, etc.).

Since its only the engine, I picked up a set of valve covers, intake manifold, and oil pan. I'm planning on reusing the 3.7 throttle body, resonator, and timing chain cover.

Am I leaving anything out? Not sure what to do about the exhaust manifold. Anyone know whether or not the cherokee manifold will fit into the liberty or if the cherokee manifold is even the best option?

 

[groundeffect]

Main Problems with install

What were the main problems with this install???

 

[tjkj2002]

What were the main problems with this install???

nobody has stuck around long enough to find out.They post pics and disapear.

 

[JeepCoMJ]

major problems;

ECM programming
Motor mounts (they do need minor machine work to actually work...holes slotted etc.)
matching exhaust up.
coolant hoses
cooling fan

I've got 2001 durango manifolds bolted up to 2004 KJ y-pipe and cats. It will fit.

Wiring is pretty easy.

As previously said, you have to have already had a 45RFE to do the swap, or convert wiring etc. over to 2002-2003 with 45RFE trans.


I've got the wiring and mounts all done, but it's been too hot to be in the shop, and I've been too busy to do the actual install part (cannot afford more than 9 hours down time on the vehicle right now)

 

[groundeffect]

How do I go about programming the computer. Never done one. Do I take it to a dealer? Right now my 3.7 has bad heads and I figured I could just do the swap instead. I need really find out what ****** I have though.

 

[JeepCoMJ]

How do I go about programming the computer. Never done one. Do I take it to a dealer? Right now my 3.7 has bad heads and I figured I could just do the swap instead. I need really find out what ****** I have though.

You send it off to be programmed, or have to know someone with the ability to do it. The big thing is that the 4.7 ECM needs to be programmed with the VIN# of your vehicle, as well as the security code for that VIN#. I have a friend who flashed mine for me. I have had it running on the stand, so I imagine that it should be pretty well set for install when I get there.

If you don't have a 2002, or a 2002 production model 2003 KJ, then you do not have the easy way to do this swap.

Put the heads on your 3.7. It will be much cheaper.

 

[groundeffect]

I have found a engine from 2002 Dakota with a blown head gasket for 500 but I have a friend with a dodge junk yard so I'm going up there to see what they have.

 

[groundeffect]

I'm trying to piece this together so to figure out what I need exactly.

Motor mounts from jeep grand Cherokee of the 2002
4.7 liter 2002
CPU from the liberty reprogrammed for the 4.7 liter
I use the same harness from 4.7 liter and what else do I need to do to to match to the 3.7 liter?????

I just want to be able to get it in and running and have everything in hand to start

 

[JeepCoMJ]

no, you need the 4.7 ECM reprogrammed to your KJ's vin.


2002 dakota/durango vin J 4.7 is not JTEC, it is NGC, so it will not work with a 2002/2003 liberty.

I used the 3.7 wiring harness and made my own injector harness. then just needed to swap out a few pins and connectors for the 4.7 throttle body sensors.

I don't think you should do the swap. you're going to be in over your head.

 

[new jeep owner]

sorry to high jack.
but is this a swap that could be done in a 2006 liberty ?

 

[JeepCoMJ]

as stated numerous times in this thread, you need an 02-early 03 liberty.

you could do it in an 06, but the entire wiring retrofit and conversion to a 45RFE is not worth the time.

 

[TheJawsOfDeath]

Out of curiosity, I pulled up the wiring diagrams for my 2006 and a 2006 4.7 Dakota with the 4.7. My vehicle, and the hypothetical Dakota both have manual transmissions. There are i think less than a dozen differences in the pin out of each ECM. The big ones are obviously the extra injectors and spark plugs on the 4.7, and the Dakota has EGR. Almost all of the rest of it is the same. Both ECM's communicate with their body control modules/junction module on the PCI bus. The Dakota has a straight PCI bus whereas the liberty has a hybrid bus with CAN-C being used for other modules like ABS for example. Since the Jeep's BCM is the interface between the PCI modules and the CAN modules, I suspect that the Jeep BCM would communicate with the Dakota ECM, allowing you to avoid a piggyback dual ecm setup. Of course I have no way to really verify that without the Dakota ECM, wiring harness, a Star Mobile scanner, and lots of free time.

 

[JeepCoMJ]

dakota does not have 42rle trans.

 

[ThunderbirdJunkie]

dakota does not have 42rle trans.

He said manual transmissions for both. Reading comprehension is fundamental.

Sent from ThunderbirdJunkie's mind via satellites

 

[JeepCoMJ]

so is not being a jerk.

And yeah, you could probably mount it. I have no knowledge on the manual trans, save that I wouldn't want one of them from an 02 behind a 4.7. some garbage about strength...and i've blown enough manuals with custom motor swaps.

 

[ThunderbirdJunkie]

so is not being a jerk.

And yeah, you could probably mount it. I have no knowledge on the manual trans, save that I wouldn't want one of them from an 02 behind a 4.7. some garbage about strength...and i've blown enough manuals with custom motor swaps.

Hi, pot, meet kettle.

The NSG370 is what comes behind the 4.7 Dakotas anyway. You break shit with manual transmissions, that's just a fact of life.

Sent from ThunderbirdJunkie's mind via satellites

 

[tjkj2002]

You break shit with manual transmissions, that's just a fact of life.

And why most do nopt use manuals anymore.If I remember correctly only a handfull of vehicles used a manual trans in KOH race and one of the top placers was using a stock 42RLE.

 

[Honduras]

Hey everyone.

Haven't been on the forums in awhile, but if anyone is considering taking on this project and you do not have the ability to redo the wiring harness and ECM, the folks over at hotwireauto.com can take care of it all for you. Upgraded harness & ECM programming set me back $555.00. All that I did was send them my original 3.7L harness and an ECM from a '04 Grand Cherokee 4.7L HO.

Chris Squire is the owner. He is a great guy to work with. There was excellent communication throughout the entire wiring/ECM build process.

Haven't received the package yet, but it should be here (hopefully!) this week.

The donor engine:

Edit: Yes, the engine is a completely rebuilt 4.7L HO. The HO version has 265 hp vs 235 hp in the non-HO 4.7 version.

 

[wheeee32]

Nice! Re-built is looking purdy.:happy107: