90 XJ planning stage

[XJMurray]

This is my first post here but I have been searching and reading for quite a while now. I have a 90 XJ with 4.0 AW4 NP231J, I bought the jeep running for $400 previous owner said the tranny was bad. Body is perfect no rust driven by a school teacher so all highway driving. I pulled the tranny and T-Case and bought a new tranny of a buddy doing a th350 swap for $30. The jeep has no power accessories (mirrors windows) I did not want these amenities had problems with them in past. I plan on stripping the motor down to bare bone essentials except AC to make field diagnosis easier. We have no emission testing in MO so I will be removing all emissions equipment from vehicle. I am looking into a RAD shifter so I can eliminate the TCM and manually lock the torque converter. I will be pulling and rebuilding the 4.0 and going through the AW4 for insurance sake.

My goal is a expedition type rig on 35's with ability to tackle decent trails on weekends (SMORR, Disney OK) and some mild rock crawling. This is my 4th jeep and I have played with them all and have never broken an axle component on stock drive train with 35's, I am very light on the skinny pedal. I want a very dependable rig that is mechanically sound. I want the ability to pack up and drive to moab or Colorado and have no worries.

Anyway on to the plans or decisions to be made.
removing stock axles, Front I haven't made up my mind yet, I would like a D60 so I wouldn't have to worry about breaking anything but the money for a D60 is ridiculous. I have a HP D44 out of a late 70's F150 and a D44 out of a 78 K10 I have no money in these axles so it would be nice to rebuild with bearings, some stronger U-joints, ball joints, gears and an Aussie locker and run them.

Rear full width GM14 bolt (shaved) with 4.88 and an Aussie locker.

The reason for my dilemma, I want to put a Dana 300 Transfer case in the jeep for the dependability of gear drive and ability to twin stick. I plan on using my 231 input to make a crawl box so I can have very low gears if needed without having to gear the axles really low and hurt highway usage. And by using the 231 gear box I don’t have to buy an aftermarket adapter to mate with the AW4. Since I don't want to flip the D300 and mess with all the custom (hard to field fix) stuff I am thinking passenger side diff. I know the down side to pass diffs and their weaknesses. I am wondering if I should take my HP center and put everything from tubes out from the Chevy on it. I could still run stock axles (I think), have beefier knuckles and easy to upgrade to 8 lug (to match rear)since the 78 has the larger spindle. I would still be able to find parts at any pick and pull or parts store and do field repairs.

Is there any downside other than initial setup to this axle build. I have a buddy that will press my tubes for free so there is no real cost in terms of building the housing. Or should I sell both axles and find a pass drop Chevy D60 and put it in and not worry about it.

I plan on running 35's with minimal lift and body trimming for better stability. I don't plan on running any larger than 35” tires so I think the D44 should hold up. I will be doing a mild exo, rock sliders, frame reinforcement, and some body armor so there will be some additional weight other than all the gear. Jeep will keep 4 passenger seating.

Any input will be greatly appreciated and I expect some flaming so no worries. Hoping you guys can help me decide whether to run the pass drop D44, Hybrid Pass drop HP D44 or Pass Drop D60. And any other concern you have about what I have listed so far.

 

[BEVAN]

Better have deep pockets...35's + plus axle upgrades = $$ ~ on a 90 XJ...stripping it to bare bones engine wise is kind of hard to do...they are pretty bare bones as is are you planning to drive this jeep to the trail or trailer it ?

 

[XJMurray]

If I can use the axles I have, I wont have any more in them that setting up the stock axles. I will be using leaf springs in rear and building the front suspension myself which will be like a Rubicon Express long arm kit. I want to have the ability to drive it anywhere but I have the option of towing if needed.

 

[BEVAN]

The problem with switching axles and modifying (other than well designed lift kits) a vehicle from its original state is it can become unreliable and suck to drive...Since most expo miles are on hwy its something to consider.

 

[Topgun514]

Renix engines are pretty much already stripped down. Take out EGR, thats about it.

 

[XJMurray]

Renix engines are pretty much already stripped down. Take out EGR, thats about it.

Thats pretty much what I have found out, I was looking for a vehicle that did not have all the electronic components but still had a form of Fuel injection. I think the only other component I am removing is the TCM and replacing it with the after market kit. My goal is to carry the least amount of spare electronic parts right now I think a spare ECM, injectors, and CPS.

 

[XJMurray]

The problem with switching axles and modifying (other than well designed lift kits) a vehicle from its original state is it can become unreliable and suck to drive...Since most expo miles are on hwy its something to consider.

I agree that there are things to consider when installing non OEM axles, I am not building a custom 4 link or rock crawling suspension. I am just replacing stock axles with wider axles. I am using the same suspension set up in the rear and using a aftermarket (bolt on) style suspension for the front I will just build it myself. One of my wheeling partners has a RE 4.5" long arm lift and we will be using it for measurments I have seen it work on and off road and it handles very well on the highway at high speeds. My biggest hurdle is going to be the steering setup to make it very roadworthy. I will be using wheels with correct backspacing to keep the width to a minimum.

I really don't see how a full width setup (other than steering) is different than someone pulling a waggy D44 that is the stock width cutting all the OEM hardware (leaf springs) and mounts off of it, and mounting it in the stock location with all the new vehicles stock hardware (coil springs).

 

[Topgun514]

You might wanna take the AC out. Old style sucks and does not last long anyways. I do not have it in Utah in a Black jeep- temps get to 110. Thats why mother nature allows windows!

As of now you are building a rock crawler, you will have more hits and responses in NAXJA and Jeepforum.

What are your ExPo goals though? You will have more thoughts if you say freezer/ fridge, roof rack, your carry ideas and sleeping platforms.

 

[XJMurray]

You might wanna take the AC out. Old style sucks and does not last long anyways. I do not have it in Utah in a Black jeep- temps get to 110. Thats why mother nature allows windows!

As of now you are building a rock crawler, you will have more hits and responses in NAXJA and Jeepforum.

What are your ExPo goals though? You will have more thoughts if you say freezer/ fridge, roof rack, your carry ideas and sleeping platforms.

I do not want a designated rock crawler but I do want it capable of the type trails and terrain (lots of rock) that we have local (within 3 hrs). Because thats were I will wheel most often.

I need ac because of the humidity (and wife), on one of my previous jeeps ac didn't function and trying to keep windows from fogging up was horrible especially in the rain. I was thinking about a aftermarket air or finding a later year model that I could install but I don't know whick ones will work my previous jeep was a 98 and it went out several times.

As far as storage goes, I will build a slide out storage in back of jeep, I will integrate a roof rack into the semi exo lights will be mounted between the lateral bars of racks to keep them out of limbs. I plan on having a tow behind trailer to carry camping gear. So jeep will have to able to tow on roadway. I'm thinking about a lager fuel cell to gain longer mileage range. I also plan on zj seats preferable leather for a more comfortable interior, but i'm concerned with their height I'm 6'3".

 

[Tumbleweed]

You are going to have a hard time doing all you want in one rig. You want to crawl, do rocks, drive highway legally, and tow; all with extreme dependability. I have been in that situation several times and the answers are not easy (or cheap). Usually involves two vehicles, or altering my desires.
How will you keep it legal with full width axles? With the added weight and larger tires, how will you make it stop? Add towing to the brake issues?
I have been wheeling over 35 years and owned 17 Jeeps and several trucks over the years. My advise would be to lower your expectations. A decent XJ, with mostly stock components and on 31 or 32" tires will do most everything you want it to do. Some spare parts, some armor, and away you go. Or, get you a rock rig to beat up and another rig to travel in.

 

[BEVAN]

My advise would be to lower your expectations. A decent XJ, with mostly stock components and on 31 or 32" tires will do most everything you want it to do. Some spare parts, some armor, and away you go. Or, get you a rock rig to beat up and another rig to travel in.

Best advise so far...This is the only way to go.

 

[XJMurray]

You are going to have a hard time doing all you want in one rig. You want to crawl, do rocks, drive highway legally, and tow; all with extreme dependability. I have been in that situation several times and the answers are not easy (or cheap). Usually involves two vehicles, or altering my desires.
How will you keep it legal with full width axles? With the added weight and larger tires, how will you make it stop? Add towing to the brake issues?
I have been wheeling over 35 years and owned 17 Jeeps and several trucks over the years. My advise would be to lower your expectations. A decent XJ, with mostly stock components and on 31 or 32" tires will do most everything you want it to do. Some spare parts, some armor, and away you go. Or, get you a rock rig to beat up and another rig to travel in.

There is no problem having full width axles in MO we don't have a mudflap or fender flare law. For braking it will have 3/4 ton Chevy brakes front and rear which should do the job and electric brakes on the trailer.

I sold a TJ with 31's because it wouldn't allow me to go on the same trails as my buddy's without lots of winching. They all have 35's or larger but non are rock rigs all are full bodied DD's just very well built. I guess if I had to pick I would choose slightly more capable on the trail than on the road, I have a tow rig so that isn't a problem.

I'm not trying to argue, you have a very valid point, I just think there is differences on how you and I want them to handle on the road. I don't want it to handle like a stock rig or a car if I wanted that I would drive a stock rig or a car. I just don't want it to handle like a buggy with no sway bars and horrible steering that is a pain just to drive in one lane. I am happy with somewhere in between I am just trying to figure out the best way to get there with a very reliable rig. Much like the DRACUL jeep

I do appreciate all the feedback.