NotMatt

I'm very close to doing this swap as well and am grateful for the tips. Never swapped a fuse box before, but I think I will be doing the cut and solder/heatshrink method. I have a nice fuse box from a 89 XJ to go into my 89 MJ so I'm hoping the wire colors are going to be all the same... should be a fun little project, lol.

Clean it out with some solvent, and weld a nice hot bead around the inside of the spacer as far around as you can. When it cools, it will shrink the spacer and it will almost fall out.

This is before he tubed the front end out and painted it:

Took yesterday off work to get some stuff done on the Comanche. Started out with the spring over on the rear. I was going to put a Ford 8.8 in, but that deal fell through so I decided to go ahead and do the spring over with the D35 for now. I'm into it 30 bucks for a pair of spring pads since I ruined the old ones cutting them off. I used the stock u-bolts and spring plates, just cut the factory shock mounts off and flipped them over onto the top. The best thing about working on a Comanche... a place to put all the pieces! Today I got the rig all leveled up on the jackstands and got the 2wd axle out. As it sits right now, the bed is level. I took some measurements as the truck sat on the ground, then added 5.5" for the coils, so I know exactly where to place the D30 under there. The plan is to place the front axle on jackstands exactly where it will be at ride height with the caster set at 7 degrees so I can mock up the long arms. I dug out the one factory tow hook bracket that I have out of my parts pile. It came off an '87 XJ with tow package and skid plate package. This goes in place of the bumper bracket as you can see in the pic. Pretty easy way to have a recovery point on the front, if you can find the brackets. You have to drill a couple of holes through the uni-frame up front and run some bolts through and trim the stock rubber pieces behind the bumper/fender. Unfortunately I only have one, I lost track of the other one (maybe I gave it away lol) but I figure that's all that's really needed anyway. I think I will end up re-working this to also make it into a steering box mount re-inforcement plate similar to some of the aftermarket ones. Combine that with a steering box brace and I should have no issues with the frame cracking.

Just ordered some 5.5" Rubicon Express coils and the 1660 RE Extreme Duty trackbar and bracket, and a drop pitman arm from my friend Jeff at Rock Ridge 4WD. Parts should get here on Tuesday or Wednesday, then the fabrication begins to build some longarms and crossmember. Don't know what the status is on linking to pages here, but Google search it and you'll find it. Jeff is "one of us", this is his Comanche he built from an '89 2wd 4.0. The flatbed is all custom built and he did a leaf spring swap up front with 2" YJ leafs, Ford HP 44 and Dodge D60 rear. Junkyards around these parts think their stuff is gold plated, lol. We have a local automotive electrical shop that will sell me the parts cheap and I've done a couple rebuilds before with good results.

Well tonight was eventful. Tore the front end down. Replacing the old 2 row radiator with a spare 3-row unit, still closed system since I think they work fine if properly maintained. Removed the a/c condensor too. Tore apart the driver side of the motor. Going to put in new motor mounts, fix cracked exhaust manifold, replace injector o-rings, delete the egr and some other cleanup while I'm there. Tomorrow I'll finish this up and start in on the rear spring over. Have to wait for coils and a trackbar to do lift the front though. Also going to swap in an XJ brake balance valve so I can get rid of all the extra funny business variable rear brake valve stuff and just have one line to the rear brakes. My squeek in the belt train turned out to be the alternator, so I'll be tearing in to that to put some new brushes in and freshen it up.

So I spent some time last night replacing the serpentine belt that shredded into strips on me a few days ago while I was driving home from work. Found out it was only marginally tight from the previous owner, and half of the bolts holding the power steering pump were missing or loose. So I threw on the new belt, but I'm not convinced I solved the problem. With the belt tightened and tensioned properly, I now have a very loud "squeak" under acceleration, and a pronounced grinding noise at anything above idle. I replaced the tensioner pulley last night thinking that would solve it, but no go. So now I get to chase down whatever is squeaking and causing a ruckus in the belt train. Easy enough I guess. I have a 3-row radiator to swap in place of the beat up stock rad in there now, and some new motor mounts to go in... so I'll do all of that this weekend.

Mnkyboy: I'm in Wenatchee 87warrior: I already have them, so that's what I'll run. I plan on building a similar setup to the Clayton raddius arm kit including the crossmember with removeable center section. I had the Clayton kit on my old xj and was very happy with it.

Oh yeah, that's right. I forgot the nomenclature for 231 vs. 242. Command-Trac would be 231. In any case, it doesn't matter cause it's all getting converted anyway. :D I have an unheated uninsulated garage to work in right now in Eastern WA (it just snowed 4" last night)... is it strange that I'm still excited to get home from work and get straight to working on the MJ? Lol. I have door locks to swap cause I don't have a door key for the MJ, and a leaking tranny line to replace, as well as a new serp. belt.

An interesting fact... I ran the VIN on this Jeep through the decoder listed in the DIY/Writeup section... It came out telling me that my MJ was a 4.0, 4wd, selec-trac, with floor shift. So either someone in its past converted it from 4wd to 2wd and floor to column shift, or the VIN decoder is not accurate. The VIN is the same everywhere on the rig, and as far as I can tell it has always been 2wd unless someone was VERY meticulous in converting it to 2wd. I'm betting on the latter, that the VIN decoder is not so accurate... OR, since this Jeep is an '89 model year and was manufactured in early '89, it was built in with odds and ends that Jeep had leftover from production year '88 and still titled as an '89, and the records are just not that accurate. PS I love the smiley selection on this forum, lol.

The H4 bulb upgrade really is worth it. I ran Hella glass and Silverstar bulbs in my old XJ, and will be doing the same in my new MJ. Just make sure your headlights are aimed well, you'll get lots of angry drivers "flashing" you if you don't have them aimed properly. Losing your head light switch (and thus headlights) going 60 down the highway at night sucks. It's even worse if you're out in the woods in the middle of nowhere, you'll be spending the night if you're by yourself. Get the upgraded harness, it's really easy to install and like others said, even with stock lamps you'll see an improvement. Carry a spare headlamp switch or the proper tools to jerry-rig the lights on if need-be. :cheers:

The one bit of advice I can give you is this: Take your time. Swapping wiring harnesses is not such a simple plug and play type operation. You'll need to get one from a similar cherokee or MJ, and you may still run into plugs that don't match, parts that need to be removed to get to different pieces of the harness, etc. I would not try to drive it around while you are doing the work, because you will probably run into problems that will leave you waiting for small little parts or pieces for a few days and it may be un-driveable in the mean time. Get a good soldering gun, some heat shrink tubing, and a good wiring diagram as well. Good luck. :D

Allow me to introduce myself! My name is Matt and I am addicted to Jeeps. I own a '91 wrangler, and have owned and/or worked on various Cherokees, Comanches and Wranglers through the years. I've collected a large XJ/YJ/MJ spare parts pile, and I figured what better way to put some pieces to use than on this... She's an '89 Pioneer model, long bed 2wd with a 4.0L, AW4 automatic. Pretty bare bones, base model with bench seat. I bought this from a co-worker of mine. It has been sitting for quite a while with what he said was a bad fuel pump. It turned out the only issue was that the hose from the pump to the pump bracket/housing inside the tank had disintegrated. After some TLC, she fired up and ran like crap due to the bad gas. After trailering it home, I found all sorts of little issues that needed fixing, including missing vacuum lines, "twist and electrical tape" spliced wiring, electrical issues with the multi-function turn signal switch. The first thing on the list to fix/replace... the steering column. At some point, someone attempted to fix the multi-function switch issue and tore the steering column all apart. Unfortunately, they just threw all the parts in a bin and lost a few along the way. The stock steering column was also a "column shift" unit for the AW4, which I could leave or take. However, since I had a whole spare steering column in gray from an '89 XJ, I went ahead and swapped it in to avoid the painstaking process of having to tear down one good steering column to provide donor parts for another. Also from the same '89 XJ, I went ahead and swapped in the floor shift unit for the AW4. This is a really easy swap. You need the shift cable from a floor shifted XJ or MJ, and the shifter assembly from your donor rig. The cable attaches to the tranny the same way as the column shift one does, and pushes through the firewall through the same grommet. Just has to be routed above the steering column and over to the center floor shift instead of to the bottom of the column. When you pull the carpet up, you will find that there is simply a plate that needs to be unscrewed and removed for both the 4wd shift assembly and the floor assembly. I went ahead and disabled the lockout on the steering column that I swapped in by blocking it with a screw so I would not need to unlock the steering column to take the rig out of park, so I avoided swapping in an extra cable to the shifter for that. Stay tuned for more pictures and tech as I proceed to do a 4wd conversion. The plans are for a spring over in the rear, and a Ford 8.8 with discs to replace the D35. A non-disconnect high pinion D30 will be going in the front, and I will be building a long arm setup similar to the Clayton Offroad kit with RE joints. In the mean time, here's another pair of Jeeps parked at my house. The YJ on the left is my wheeler... 4.0HO, AX-15, Atlas 5:1, welded 14 bolt in the rear and welded Ford HP D60 in the front with full hydraulic steering. The one on the right is my buddy Dan's XJ "wagoneer", Renix 4.0, AW4, 231 with a welded D60 w/5.38 gears in the rear, spooled HP44 up front w/5.38 gears, front leaf spring conversion, and hydro-assist steering. Cheers!