89 Comanche > 88 Cherokee 4x4 swap

[89MJohn]

Total new member no posting experience any help suggestions or funny jokes appreciated!!

 

I recently was given an 89 jeep Comanche 2wd 5 speed manual. It was near a California wildfire and was saved by single lady homeowner before total loss.

 

I moved her to new home and she noticed me admiring it.

 

Longest story short her sons first car, he had passed away, she kept in memory of him. Someone stole it, punched ignition, on and on.

 

[Ωhm]

Welcome to CC Forum.

[89MJohn]

So after moving her she offered it to me.

We filled out the paperwork because she'd lost title, and I put $200 cash in her purse without her seeing just to help out. 

 

She called later and tried insist I take the money back lol.

 

Reading for 2 weeks I understand swap from a "donor truck" is bolt on with moderate sarcasm mentioned sometimes 

 

I had seen an xj at a neighbor's home so off with Cash i went.

$225 for the 88 2 DOOR xj with 219k on clock.

Started fine and drove onto trailer 

 

Leaked water from rear of engine and steering was terrible but for the $....

[89MJohn]

89 mj 4.0L manual 2x4

88 xj 4.0L automatic 4x4

 

I will get pictures of mj engine bay and wiring tomorrow 

 

Here is the xj engine bay

& here xj is out of theway after trailering home

[thecodemonk]

Nice! This sounds like the start of a good build thread! Looks like you got some good bones to put together too!

Is that grille.. melted?? With that much heat, you definitely want to replace the radiator as I would assume that the plastic sides on the radiator are probably compromised.

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[89MJohn]

Yes melted 

Prev owner pushed it away from wildfire so she could save it. 

 

Radiator will be upgraded to 91+ model with radiator cap and open system from my reading 

 

Questions 

1. Should I abandon melted mj wiring harness in place of xj harness or repair?

 

2. Should I upgrade front xj axle away from what I've read is vacuum disconnect d30 axle

 

3. I'm self and internet educated automotively and want to know if I'm over my head before hand

[Dammerung]

Yes melted 
Prev owner pushed it away from wildfire so she could save it. 
 
Radiator will be upgraded to 91+ model with radiator cap and open system from my reading 
 
Questions 
1. Should I abandon melted mj wiring harness in place of xj harness or repair?
 
2. Should I upgrade front xj axle away from what I've read is vacuum disconnect d30 axle
 
3. I'm self and internet educated automotively and want to know if I'm over my head before hand

Welcome to the club!

1. I’d recommend replacing everything with the stuff from the xj, as most of the connectors for the headlights and such are melted.

2. I can’t help, 4 wheeling isn’t my thing.

3. I don’t believe you are. The Comanche is my first and I haven’t had any problems tying to fix mine up. It should be a simple in and out swap with the good parts from the xj


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[Smokeyyank]

Welcome and good find! For the harness you got 2 routes. Upgrade to a 97 xj+; advantages are better connectors, obd II, and parts more readily available. Disadvantage it's a lot of work. 

 

Or

 

Swap in another renix era harness. Advantages; not as involved as a 97+. Disadvantage you're still going through a decent amount if work for little gain, connectors could be a problem. 

 

Axle if you're already planning to swap I'd find a non CAD d30. Plus the 96+ have bigger u joints.

 

No, not only is CC an awesome forum full of tons of knowledge but there are  plenty of write ups on swapping  to a 4wd and so on. Anyone with some basic mechanical aptitude can easily wrench on a 4.0.

[Eagle]

11 hours ago, 89MJohn said:

Yes melted 

Prev owner pushed it away from wildfire so she could save it. 

 

Radiator will be upgraded to 91+ model with radiator cap and open system from my reading 

 

Questions 

1. Should I abandon melted mj wiring harness in place of xj harness or repair?

 

2. Should I upgrade front xj axle away from what I've read is vacuum disconnect d30 axle

 

3. I'm self and internet educated automotively and want to know if I'm over my head before hand

 

 

1. Is the MJ harness melted? If so, the XJ harness should be pretty much the same, so you should be able to use all or most of it to replace the damaged parts in the MJ. The biggest difference is that the '88 has the C101 connector -- high on the firewall, on the driver's side in the engine bay. That's where the engine side mates with the under-dash part. The C101 connector was troublesome, and for the 1989 model year they eliminated it.

 

2. Unless you plan to run huge tires, there's nothing wrong with the D30 axle in the XJ. Just engage the disconnector and lock it in place -- there are several articles here explaining how to do that. There's no reason for you to buy another axle if you already have one. Just be certain the ratios match.

 

3. You'll learn a lot. We're here to help when you have questions.

[DesertRat1991]

13 hours ago, 89MJohn said:

89 mj 4.0L manual 2x4

88 xj 4.0L automatic 4x4

 

I will get pictures of mj engine bay and wiring tomorrow 

 

Here is the xj engine bay

& here xj is out of theway after trailering home

 

 

But... that XJ tho... 

 

Are those the original Marchal fogs?  How's the interior look?

[89MJohn]

1 hour ago, DesertRat1991 said:

 

 

But... that XJ tho... 

 

Are those the original Marchal fogs?  How's the interior look?

Lol

My same thoughts exactly

2 DOOR bone stock down to fog lights accept that spare carrier which is growing on me.

Interior is good missing passenger door card and DIRTY. Headliner is good, nice dashmat

 

Found several tools & three boxes of ammo in xj so knock another $25 off price 😀

 

My cousin dibbed the carcass for a chevy 4 link swap IF I gut it. 

[89MJohn]

1 hour ago, Eagle said:

 

1. Is the MJ harness melted? If so, the XJ harness should be pretty much the same, so you should be able to use all or most of it to replace the damaged parts in the MJ. The biggest difference is that the '88 has the C101 connector -- high on the firewall, on the driver's side in the engine bay. That's where the engine side mates with the under-dash part. The C101 connector was troublesome, and for the 1989 model year they eliminated it.

 

2. Unless you plan to run huge tires, there's nothing wrong with the D30 axle in the XJ. Just engage the disconnector and lock it in place -- there are several articles here explaining how to do that. There's no reason for you to buy another axle if you already have one. Just be certain the ratios match.

 

3. You'll learn a lot. We're here to help when you have questions.

Eagle, and to EVERYONE above

 

THANK YOU FOR YOUR TIME 

 

So helpful to have direct answers especially with subtle year model differences like the wiring plug c101 mentioned 

 

To do away with the c101 plug I can direct solder the wires and do away with it myself from 88 harness??

 

So I see both opinions, replace and repair the in fact melted mj harness or abandon it... Pics of the mj wiring damage should help with decision. Will post later

 

Concerning the 97+ swap, price difference leads me to the -91 year swap. I can't find a 97 for under $1700

[89MJohn]

Mj engine bay

 

Not sure its melted wiring, thinking its a few wires that direct shorted and a bad mechanic took it all apart.

[omega_rugal]

oh that feeling when you see an MJ waiting to be modded...

[Eagle]

8 hours ago, 89MJohn said:

To do away with the c101 plug I can direct solder the wires and do away with it myself from 88 harness??

 

 

Yes. In fact, the factory issued a TSB (Technical Service Bulletin) recommending exactly that.

[89MJohn]

What's the consensus on wiring mess?

 

Excellent I will Google the tsb for the plug solder repair.

 

Anything else like that i should be aware of?

 

Decided to keep the 2 door xj complete for wife and find another 88-91 donor xj

[Eagle]

12 minutes ago, 89MJohn said:

Decided to keep the 2 door xj complete for wife and find another 88-91 donor xj

 

Donor can be '87-90. 1991 was when Chrysler introduced the HO. Those have a totally different electrical system. Different ECU, different injection, different ignition.

 

Assuming the XJ is complete and undamaged, you can open the hood on that and use it as a road map to check what's been messed with in the MJ.

[Pete M]

how solid is that XJ?  how much work to get it working again?  those things are pretty dang rare and I'd wager you can make a tidy profit if it's easy to get running again. 

[Eagle]

1 hour ago, 89MJohn said:

Decided to keep the 2 door xj complete for wife and find another 88-91 donor xj

 

 

Good plan.

[89MJohn]

So create a new page for the xj fix up or keep on truckin here everyone?

 

Xj questions and apologies in advance for poor photos

 

Is this the c101 plug high on firewall that needs direct soldering, drivers side? Also in same pic near bottom is a rubber hose with a white plug. Is that supposed to be plugged?

Hey posting is easy....

 

Next, looking above throttle body

Whats the unplugged 2 wire plug center of pic

Also what's the steel cable directly under the 2 wire plug. Old cruise control? Interior has aftermarket cruise unit 

[89MJohn]

Final ask for help of the evening 

Hose from thermostat is broken hence water leak 

I see where one hose plugs into, where does one with green arrow go?

 

Will these be replaced with open cooling system upgrade?

Thank you everyone again for the warm WELCOME 

[jdog]

So create a new page for the xj fix up or keep on truckin here everyone?
 
Xj questions and apologies in advance for poor photos
 
Is this the c101 plug high on firewall that needs direct soldering, drivers side? Also in same pic near bottom is a rubber hose with a white plug. Is that supposed to be plugged?
Hey posting is easy....
 
Next, looking above throttle body
Whats the unplugged 2 wire plug center of pic
Also what's the steel cable directly under the 2 wire plug. Old cruise control? Interior has aftermarket cruise unit 

Yep thats the 101 connetor, the hose with the plug is the vent for the front axle and is supposed to have the cap on it. I'm not sure where the plug in goes, yes I would say that's a cruise cable

Stock 1988 swb 4.0 ax15 np 231.

[jdog]

Final ask for help of the evening 

Hose from thermostat is broken hence water leak 

I see where one hose plugs into, where does one with green arrow go?

 

Will these be replaced with open cooling system upgrade?

Thank you everyone again for the warm WELCOME 

That hose will go to the coolant bottle, in the picture you almost see where it was broken.

 

Stock 1988 swb 4.0 ax15 np 231.

 

 

 

[89MJohn]

1 hour ago, jdog said:

That hose will go to the coolant bottle, in the picture you almost see where it was broken in the picture

Stock 1988 swb 4.0 ax15 np 231.
 

Now I feel dumb, I was looking for a hose connection to fit it with. Wow that 101 connector has a lot of wires!! Do all wire colors match either side of connectors or follow pins direct 1 at a time?

 

 

[jdog]

Now I feel dumb, I was looking for a hose connection to fit it with. Wow that 101 connector has a lot of wires!! Do all wire colors match either side of connectors or follow pins direct 1 at a time?
 
 

No problem it's a weird setup. I am not sure with the 101 connetor as I have yet to do it. If you look on cruisers website, cruiser54.com he has instructions on how to delete it. Oh and welcome to the club.

Stock 1988 swb 4.0 ax15 np 231.