4.0 Entire Driveline Swap

[firewire79]

Greetings from Afghanistan. I am going to buy a 82-86 CJ7 when I get back, and have looked into getting a fuel injected
option for reliabilty, economy, and off road advantages.

So, I have been doing my homework regarding the 4.0 swap process. I have decided to go the swap route as it appears
to be less expensive the MOPAR option or the Howell kits. Plus I get the MPFI over a TBI.

I have found that a 4.0L from the following units will be the best choices:
91-95 XJ
93 ZJ (Grand)
91-92 MJ (Like I can find a Commanche)

The reason for these selections is that I can avoid any sort of OBD-II issues when it comes to wiring. That, and supposedly,
the motor mounts line up directly, so there should be little modification to get the driveline in.

All these models came with either the AW-4 AT or the AX-15 MT and the NP231 Transfer Case . I am hoping to be able to use
a AW-4 so that my wife can drive the Jeep from time to time. If the AW-4 is not a viable option, the AX-15 poses no problem
for me, other than teaching the wife to drive stick.

If I decide to go the junkyard pick and pull route, which is my plan, will there be any issues with space if I go with the
AW-4 and NP231, as most Cherokees were automatic. Or is it in my best interest to use the Dana 300 instead, due to space
restrictions.

I am aware that the AW-4 is fairly long, so if it won't work, so be it.

I know that if I keep the Dana 300 Transfer Case , I will need an adapter from Novak, and using either the AT or the MT, I will need
a 91 YJ speed sensor.


Basically, the short question is this. If I pull an entire drivetrain, engine, Transmission , and Transfer Case , from a Cherokee,
will it bolt right in? Reltively speaking of course, I know there will be wiring issues and minor tweaks to get it running. I am
a fairly compotent mechanic, but having a plan always makes things go better.

Thank you for all your advice in advance. The more homework I can get done now, before I dive into doing an engine swap,
the better.

 

[hole]

A Cj has a passenger side front driveshaft drop, and the Xj is drivers side drop. You'd be better to get the Novak adapter and use the Dana 300 and leave the front end alone. Too bad your on the other side of the world right now, I have a 94 Xj that runs like a top that was just totaled. Thank you for your service atriot:

 

[73jeep]

Have you thought about a YJ with a CJ front clip and dash swap?

Same look but without a engine swap.



Sent from my SCH-I545 using Tapatalk 2

 

[firewire79]

I did think about that, but it's not the same. It will be missing the classic dash, and, worst of all, I will know that its a lie. No offense to anyone who has done that. I suppose its no worse of a lie than a 93 4.0L in a CJ.



Hmmmm.......Maybe I should reconsider.......



If there is a way to get the classic CJ dash into the YJ, it may be a real possibility.

 

[yellow85cj]

Been done more than you would think. Here's an old write up. Google dash swap and can probably come up with more.

Swapping a CJ Dashboard Into a YJ: Off-Road.com

 

[Sasquach]

Seems like Your getting ahead of yourself to me. Since you have not yet purchased a CJ you can not know what motor or what condition it will be in, but....if it were to come with a solid AMC 258 i6 / 4.2l engine why not save allot of work and expense and just do the 4.0 head and injection system to the AMC 258 i6 / 4.2l ?

 

[firewire79]

The aftermarket kits for EFI added into a AMC 258 i6 / 4.2l are fairly high priced, any where between $1100 and $2300. If there is a viable junk yard EFI option, that may be a better choice. No matter the condition of the AMC 258 i6 / 4.2l , I do a fair amount of off-roading and am heistant to deal with the headaches of a carb'ed engine. Stalling out while doing hill climbs and rocks doesn't really sound like the best option for me, and I know that I can go with either a junkyard 4.0 swap or an EFI kit to remove that headache.

The only reason I haven't considered doing the 4.0 head onto the AMC 258 i6 / 4.2l is that I read several articles on here stating that they had problems with the swap itself, and ran over the cost of a swap by the end of it.

If I go the swap route I can continue to drive the CJ until the 4.0 has been cleaned up and rebuilt and is ready to be installed. I should be able to doa majority of the engine work myself, provided I grab all the FSM that I can find for specs on everything.

 

[ThisGuyUKnow]

Greetings from Afghanistan. I am going to buy a 82-86 CJ7 when I get back, and have looked into getting a fuel injected
option for reliabilty, economy, and off road advantages.

So, I have been doing my homework regarding the 4.0 swap process. I have decided to go the swap route as it appears
to be less expensive the MOPAR option or the Howell kits. Plus I get the MPFI over a TBI.

I have found that a 4.0L from the following units will be the best choices:
91-95 XJ
93 ZJ (Grand)
91-92 MJ (Like I can find a Commanche)

The reason for these selections is that I can avoid any sort of OBD-II issues when it comes to wiring. That, and supposedly,
the motor mounts line up directly, so there should be little modification to get the driveline in.

All these models came with either the AW-4 AT or the AX-15 MT and the NP231 Transfer Case . I am hoping to be able to use
a AW-4 so that my wife can drive the Jeep from time to time. If the AW-4 is not a viable option, the AX-15 poses no problem
for me, other than teaching the wife to drive stick.

If I decide to go the junkyard pick and pull route, which is my plan, will there be any issues with space if I go with the
AW-4 and NP231, as most Cherokees were automatic. Or is it in my best interest to use the Dana 300 instead, due to space
restrictions.

I am aware that the AW-4 is fairly long, so if it won't work, so be it.

I know that if I keep the Dana 300 Transfer Case , I will need an adapter from Novak, and using either the AT or the MT, I will need
a 91 YJ speed sensor.


Basically, the short question is this. If I pull an entire drivetrain, engine, Transmission , and Transfer Case , from a Cherokee,
will it bolt right in? Reltively speaking of course, I know there will be wiring issues and minor tweaks to get it running. I am
a fairly compotent mechanic, but having a plan always makes things go better.

Thank you for all your advice in advance. The more homework I can get done now, before I dive into doing an engine swap,
the better.

You know an ax15 is not your only tranny option. You could also use a nv3550 or nsg370 (6speed) as they are natively compatible with amc engines.

Also an option you haven't mentioned is that you can get a Cj with the AMC 258 i6 / 4.2l an swap the head with a jeep 4.0 and use then use the fuel injection to run the AMC 258 i6 / 4.2l .

As for yj with a Cj front clip being a lie. The two jeeps are almost the same vehicle. The tubs are identical with the exception of how the tail gate mounts. I wouldn't poopoo that idea away because of you get a yj with the drive train you want then you can avoid a lot of headache. Although the 4.0 and ax15 are compatible you have to work out issues such as the clutch articulation and clocking of the Dana 300 .

 

[NorthwestCJer]

If you have any engine issues internally, an aftermarket Fuel injection system will be very hard to tune and keep running correctly. I love my 2100 carb and it does not stall or hesitate offroad. I spend more time screwing around with other peoples menagerie's offroad than my own.

I also think you are getting way ahead of yourself. A 82-86 CJ7 can have bigger issues than the components you are looking at. AMC20 two piece axles, 2.72 gear ratios, cracked / rusted out frames, wiring issues, etc.
You are going to spend 5-10k on a decent CJ7 and then another 5-8k on mods.
Myself, I think you should go with a TJ. I am a CJ guy, but they are not for everyone. I have seen lots of people want the "older, nostalgic look" but they don't have a clue what they are getting into, and how much work they can be.



Good luck

 

[firewire79]

Had a TJ. Loved it, especially since it was a Rubi. Had to sell it.

It was almost to easy to wheel, and I have always loved the classic look of the CJ. The only reason the I am considering the swap is for the reliability of the 4.0 engine. IF, if I can find a strong AMC 258 i6 / 4.2l , then I will pursue the 4.0 head swap. Since I expect quite a few headaches from buying a 30 year old vehicle, I am less concerned with the engine than I am with the frame and body conditions.

I can do engine work, its literally what I do. Body work on the other hand, that is a skill that I don't posses. CJs seem to come in 3 conditions, fully restored, and costing a fortune. Full on project, tub rust, no engine, you know the kind, and who knows what headaches your going to inherit with that. Or last, ones that have been started and forced into sale. That's what I'm hoping to find.

I already plan on traveling all over to inspect CJs long before I sign any documentation. I literally will fly from Virginia to California just to look before I purchase. I know it sounds silly, but I would rather be out the $400 round trip plane ticket over being stuck with a lemon of a CJ.

 

[thiswontbetooexpensive]

Don't let the AMC 258 i6 / 4.2l make you run off. The one that was in my 1980 CJ5 had not been touched in 33 years. $1,200 later it should perform brand new, or better. An HEI saves you the most troublesome parts I have been told, and I followed the advice and have went that route. I drove mine 25 miles the day I took the battery off and started taking it apart. Not very strong, but it ran and would still spin tires on dirt roads. The PO is a good friend of mine that just didn't put a lot of thought into maintenance of anything; still doesn't...

That engine didn't even have a spun bearing in it, not one. Won't win a lot on the 1/4 mile track without more $, but it will drive that CJ through a house and up the tree on the other side while churning 38" tires on 4.88 gears if you so desire. I decided against the 4.0 head swap for a couple reasons personally. Some talk about making a true stroker out of it, there are write-ups here on that as well. If you care to throw that much money at it; you can buy a complete basketcase CJ, farm out what you don't feel comfortable doing work wise, and buy the best parts money can have that you "need" and still be into it for less than have the price of a new "Rubi". Nothing against them, just not really for me and a lot of others here I would bet on the Jeep-CJ forum.

You sound plenty capable AND your service is much appreciated.

 

[firewire79]

My thought process went like this. If I can pull an engine and transmisison for, lets say $1000, why not just go ahead and use that from the get go. To get it rebuilt, I expect to spend about another $1000 for the rebuild of the engine and the Transmission .

That puts me a $2000 to drop in a 4.0HO MPFI engine in from the get go. Instead of tackeling a Howell system, which runs over the $2300 mark, or one of the more affordable kits, at around $1400, why not just bite the bullet up front and do an engine and tranny swap from the start?

The only other option that I have considered is a junkyard EFI system. But then, you are relying on the parts being in good working order when you pull them. The 4.0 head on the AMC 258 i6 / 4.2l seems like a good plan, and one that doesn't go without some consideration. But, if I can drive the CJ with the AMC 258 i6 / 4.2l in it while I rebuild a new engine and tranny, why shouldn't I go that route?

 

[Kane]

You are missing alot of details in the price swap. Take that $2000 and double it. After you just "drop it in" then you need to get $600 worth of driveshafts, $2-300 dollar Dana 300 adapter, spend another couple hundred on the fuel delivery system, new exhaust and then add up the nickel and dimer parts that you decide to change while you are in there. It gets pricy quickly. Also the 4.0 will not have the torque advantage of the AMC 258 i6 / 4.2l for crawling. If you do the head swap you retain that advantage and get a better flowing head for little money. Just my thoughts.

 

[jdarg]

Something to consider...XJs have the Transfer Case clocked down quite a bit - I believe the actual clocking is in the rear housing of the Transmission and the 231's are all the same. Not sure about the ZJ. The YJ's are clocked much flatter.

 

[NorthwestCJer]

xj's, yj's, tj's are all drivers drop.. CJ's are passenger. that's why you will need a Dana 300 or Dana 20 instead.
Are you good with wiring? Any fuel injection system will require the donor vehicles computer and either an aftermarket wiring harness or you will have to use the donor harness and do some major cleaning and adapting.
Take the advise these guys are giving you. They are experienced guys that have done swaps.
Most of us have learned the hard way about what things cost.


"JEEP"...just empty every pocket!

 

[IOPort51]

Tell me again who it was that told you the AMC 258 i6 / 4.2l was unreliable??

I know that where you are right now you need a big distraction and the more complicated the better, but the simpler the better.

There is really no significant advantage to MPI over TBI, and a 4.0 head with a GM TBI is truly a creative endeavor that won't break the bank.

 

[ThisGuyUKnow]

Tell me again who it was that told you the AMC 258 i6 / 4.2l was unreliable??

I know that where you are right now you need a big distraction and the more complicated the better, but the simpler the better.

There is really no significant advantage to MPI over TBI, and a 4.0 head with a GM TBI is truly a creative endeavor that won't break the bank.

IO you know my stance on MPI. I would totally do a junkyard MPI on a AMC 258 i6 / 4.2l with a 4.0 head before I did a TBI. Best upgrade I ever did on my old cj

 

[firewire79]

As for wiring, its the other half of my job. I read technical blueprints and schematics for fun, or at least for work. I can wire a harness.

Getting the 4.0 head on the AMC 258 i6 / 4.2l is the other project that I am considering. I was aware of the adapter for the NP231 to the Dana 300 . Rebuiling a block, generally, isn't that bad, provided the valves, springs, and bearings are still re-usable.

I'll continue my research on the project. If I can get the benefits of a MPI on the AMC 258 i6 / 4.2l , that seems to be a solid route. It's not that the AMC 258 i6 / 4.2l is unreliable, its that with some of the crawling that I have done in the past, I have seen carb'd vehicles stall out due to angles. And that is something that I would rather not have to deal with.

Let's be honest, working the clutch, the brake, the hand throttle, and all the other things that go on with rock crawling, worrying about my engine choking out should not cross my mind.

And as for listening to you guys, don't worry. If I didn't want advice on the common pitfalls and problems related to the swap, I wouldn't be here asking for advice.

 

[IOPort51]

I would not swap the entire drive train or even the engine to get MPI over TBI.

Carter carbs are a bit undependable but that is so easy to remedy that it is hardly worth discussing as an issue any more.

IO you know my stance on MPI. I would totally do a junkyard MPI on a AMC 258 i6 / 4.2l with a 4.0 head before I did a TBI. Best upgrade I ever did on my old cj