School me on XJ's

[4wdhunter]

I'm looking to buy a Jeep XJ for a driver/wheeler/camping rig. I know a little about them, but not enough. Was hoping you all could let me know what to look for and what to avoid, problem areas, etc.

This won't be my only mode of transportation, but I will road it to all trails and occasionally to work. Trailer Queens are a thing of my past.

What say you?

Thanks,
Mark

[Hypoid]

Less is more! The only thing worse than building a uni-body, is trying to sort out a uni-body that has been hacked by some teenager who wants a "bad-ass Jeep!"

[4wdhunter]

Thanks for the response.

Can you elaborate on "hacked"? Like what to look for? I'm new to unibodies...am used to body on frame.

[Stu]

There are two rectangular channels that run along the underside of the unibody (these are instead of a separate frame). Check these closely for cracks, dents, and especially shoddy repairs. Unibody stiffeners (steel angle) are commonly welded to these channels, and it would be smart to avoid a jeep that has already had this done unless it is apparent that they were done well. It would also be important to inspect the channels/rec tube up front, especially around the steering box, and upper coil spring locations. The unibody is made from much thinner steel than a standard frame so it would be a lot easier for an inexperienced fabricator to do some unintentional damage.

[EKXJ87]

I think "hacked" is a watch out for poorly lifted or modified XJ,
I've been through 2-XJ's the 1st was an 84 with a 4-cylinder/stick that I got for "free" they say you can drop a 4.0 if you massage the rear fire wall which was a PITA but doable then come to find out the 4.5 BDS LA kit will only fit a automatic base XJ. So I would 1st check and see what type of lift if any you might be looking at and check the model they fit and would start from 87 w/4.0 and newer.

The Uni-body seems get a bad wrap but a set of frame stiffeners is a cheap fix and you can get them here locally or build your own, I would look a floor rust "check under the carpet", door hinges especially 2-doors, and if the rear are leafs check the front bracket I've seen some rust around the brackets that could cause issue's but is repairable and no wrecked or SALVAGE TITLE

There are a few members here along with myself that just purchased XJ's for "another" build. Bottom line is starting with a good solid base all other parts can be found at the junk yard or made depending on your skill base. I'm located in Frederick if your ever near by and would like to talk XJ's Here are a couple of links http://jeephorizons.com/tech/xjstockspecs.html

http://www.fourwheeler.com/how-to/131-1003-jeep-cherokee-xj-build-advice-information/
http://www.fourwheeler.com/project-vehicles/154-1001-jeep-cherokee-buyers-guide/

[4wdhunter]

Thanks all. Very good information.

[dieseldoc]

The biggest thing about the unibody is no buying something that has been hit.

Again look for the tell tail dents and cracks.
If you see a rust line in the paint, it's a crack.
The front steering and spring mounts are susceptible to damage are mentioned above the uni body is thin.
The next place is the rocker panels, they are part of what keeps things strong.
Dents here are bad as well.
Body lines, pay attention to the gaps around the doors.
If there not equal then something is bent.
Same with the tailgate, the rear is twisted.

Spring mounts take a beating, be it the coils or the leafs.

Next is axles, the front gets a high pinion D30 in the later years, as well as the Chrysler 8.8 in the rear.
The early ones got the low pinion front and a D44 with the 4.0l or D35 in the 4 banger.

[husky390]

I'm a newb to Jeeps as well but here are some things I've learned while working on mine.

94 and earlier have single diaphragm boosters so less braking power. but you can upgrade to a newer booster/master.
If it's a Dana 44 axle, check if the seals are leaking, if they are, you're going to spend about $85 a side in parts plus they have to be pressed on.
Window motors are about $100 a pop
91 and newer has an open coolant system. 90 and older have a closed system but can be upgraded to open.
Valve covers leaking oil are common. Lifter noise common.
Front brake pads wear divots into the steering knuckles. Easy fix if you have a mig welder and grinder.
Pull the fan shroud to replace the water pump, especially if you have fat hands. It can be done installed, but not fun.
Make sure the main grounds are rust and oil free if you get a Renix.

Welcome to the tinkertoy of vehicles. They're stupid easy to work on and parts are cheap and plentiful.

[Hypoid]

Can you elaborate on "hacked"? Like what to look for?The gist of my comment is to look for a pavement queen and start with a clean slate. If you have a strong mechanical/engineering background, don't hesitate to look at built XJs.

That aside, there are a few things that are unique to different model-years:

'87 to '90 are pre-OBD. They have no memory, no check engine light turning on because the ECU had a problem, no "codes" are ever set. If you want to troubleshoot this system, you will develop a firm grasp of electrical controls and diagnostics.
They are also likely to have the infamous CAD front axle. The downfall of this system is Murphy's law: More parts and systems to fail. Other brands used vacuum motors to activate the front drive axle, they failed also. The rear axle was a Dana-35, unless you walked into a dealership and ordered the tow package with a Dana-44.

'91 to '95 are OBDI. You can pull into any auto-parts and have the codes read. There are many changes through this time span, but it is late, and my alarm clock sounds-off early.

'96 & '97 are change-years: Many parts are specific to the model-year. See the above comment about the alarm clock.

'98 & '99: Some think these are the best years for reliability and cost of replacement parts.

'99 to '01: Chrysler got even cheaper, emission requirements got even more expensive.

It is bed-time for this ol' geezer. :)

[4wdhunter]

Thanks for all the good information. I'm hoping to find something already partially built (lift, tires, etc.) to try and keep the build costs down. I'm a decent wrench, can weld and fab a bit too.

Once I find a suitable vehicle I will post pics, and eventually a build thread.

Keep the advice coming. And thanks again.