XJNewb Crash Course

[OutkastBoss]

[FONT=&quot]----What is this all about?[/FONT]
[FONT=&quot]Ok Naxja I have been having people asking me for advice while they look for an XJ.[/FONT]

[FONT=&quot]Before I started giving out bad advice I thought I would take everything I think I know, combine it with some searching and get it all into one place I can refer them to.[/FONT]

[FONT=&quot]If some of you guys share some facts and opinions on things I didn’t think of or was wrong about this will help me learn as well.[/FONT]

[FONT=&quot]What mileage is acceptable?[/FONT][FONT=&quot]
I would say anything under 100,000 is going to be hard to find and likely overpriced.
I would look in the 150-200, range if I had a few bucks.
It is not unusual for an XJ to Run 250, to well over 300, on factory Drivetrain
[/FONT]
[FONT=&quot]What are some things to check for on Xj’s in general?[/FONT]
[FONT=&quot]One thing to look for is cracks in the unibody, at the steering box, and Trackbar mounts.

Rear main seal leaks seem to be fairly common as well.[/FONT]
[FONT=&quot]Other than that just check for the stuff you would on any vehicle.
[/FONT]
[FONT=&quot]What is the best year to look for?[/FONT]
[FONT=&quot]This is a VERY loaded question that has been covered in depth quite a few times here on Naxja if you search there is plenty to read, however here is what I found when I looked and what I know from having an 85 and an 01 XJ.[/FONT]

[FONT=&quot]XJ's range from 1985-2001 :[/FONT]

[FONT=&quot]I own an 85 xj woody we call the Spare’Okee! [/FONT]
[FONT=&quot]I honestly don’t know much about it except it is roomier, has comfier seats than my 01 and is tough as nails. [/FONT]
[FONT=&quot]The P.O. told me it sat in a farmers field for like a decade before he got it and all it needed was some hoses and a battery. It looks and runs a little rough but it always runs. Ymmv.[/FONT]
[FONT=&quot]
The 87-90 ECU is called "Renix", it does not store Codes you use a multi meter to read and diagnose. [/FONT]
[FONT=&quot]Apparently easy to work on with a reputation for being the longest lasting XJ but they are older than dirt and people seem to spend a lot of time keeping them running due to failed sensors.

Some of these Old 87-89 Xj's have a stock Dana44 But they are rare and not too much stronger than the readily available 29 spline, 8.25 found in a LOT of later XJs.
[/FONT]
[FONT=&quot]91-96[/FONT][FONT=&quot] The Renix system went away and the inline-six got a head that flowed better, making it the "high output" motor which might be the most powerful inline-six of the bunch.

'91-'93 Are apparently good years for renix Xjs.
With a closed cooling system, no vacuum disconnect front axle, improved power and electronics in the engine.[/FONT]

[FONT=&quot]I did see some saying the 95 was their pick for best year but they didn’t elaborate as to why.

I like the 97-01 Models Often referred to as "Late Model" Xj's
They have Larger 760x U-joints in the front D30, and the Larger 29 Spline Shafts in the rear Chryco 8.25.

The 97 Models might be good to Avoid due to wiring harness changes as there were at least 3 major wiring revisions making these confusing to work on.

98-99 XJ's without ABS Is generally accepted to be the best years of the Late model Xj's and possibly the best of the XJ's as a whole.

A low mileage 99 with a 4.0/AW4/231/8.25 29 spline is about the most rock solid combo you can get with an XJ.

Of the changes made in 00-01 Xj's only one is a major concern. [/FONT]
[FONT=&quot]
00-01 have a Coil rail ignition system that is supposed to be more reliable than a distributor with much better resistance to water and a longer service life w/o maintenance.
I believe I read somewhere that this gives a marginal increase in H.P., torque, and M.P.G. with this setup.

They are however expensive to replace if they need replacing and are sometimes blamed for misfire codes when they are not functioning 100%

00-01 got the Low pinion Dana30 That is a bit weaker due to the direction the gears need to be cut for a L.P. and cause a loss of pinion clearance and slightly higher driveline angles.
This is not a deal breaker, if setup properly, your Driveline angle wont be an issue. People that run these don't seem to complain about pinion clearance issues either.[/FONT]

[FONT=&quot]00-01[/FONT][FONT=&quot] the intake manifold has a "heat soak" issue that can cause random misfires. Chrysler released an insulator that was supposed to help but people seem to think the use of a Fan timer to Cool for a few minutes after shutdown prevents this problem. [/FONT]
[FONT=&quot]People often combine a fan timer with hood vents with good results.
[/FONT]
[FONT=&quot]Some 00’s and all 01’s[/FONT][FONT=&quot] have a California emissions setup with two pre-cats and 4 oxygen sensors that like to throw codes and run hotter and sit just under the area of the intake that gets hot compounding heat soak issues.[/FONT]
[FONT=&quot]
[/FONT]00-01 came from the factory with the "infamous" 0331 cylinder head, which has a defect between cylinders 3-4. Certainly not all of these heads will crack, but enough do to cause concern.

Chrysler redesigned the 0331 head in 03 and they can be found by a marking between the 3rd and 4th cylinder that reads TUPY. You can pull the oil fill cap and use a flashlight to verify the TUPY marking.
Some swap in the TUPY or one of the aftermarket redesigned 0331 heads as a precaution.

My Opinion on Best year
I personally would recommend looking at 98-01 Xj’s preferring the 98-99.
However if I was looking I would be looking for an 00-01 since I already have an 01.

In the End I Think ANY year XJ in Good shape is worth building and With Sites Like Naxja you can see tried and true methods to make any year XJ a Great Vehicle that can be built to Perform!

[FONT=&quot]What if I find one with a cracked head?[/FONT]
[FONT=&quot]If you are up to the task it might be worth it for you, It is not that hard but it is time consuming, I recommend doing some searching and learning more but here is a good start.[/FONT]
Here is great Video Showing what you would be getting into it isn't hard but it is time consuming. http://www.youtube.com/watch?v=29I5fNAv-8M
There is also some great info in here from a guy asking questions as he did his. http://www.naxja.org/forum/showthread.php?t=1105565
[FONT=&quot]
Options.[/FONT][FONT=&quot]
Some of the things that were stock options are kind of randomly just on some Xj’s and[/FONT][FONT=&quot]Some of them came in packages.[/FONT]
[FONT=&quot]
The up country option had higher suspension, skids, and front tow hooks.
Or the tow package option with rear hitch and Aux Trans Cooler
And the police/Forestry Xj’s with extended idle switch search light and rubber floors.. [/FONT]
[FONT=&quot] If you end up with stock skids they are worth using except the transfer case skid is easy to get hung up on and most people seem to think the front skid is useless. Rear hitch and front tow hooks would be a cool stock option to find.[/FONT]
[FONT=&quot]
If you plan on building your XJ most of this would replaced with better parts anyway, and I would consider them as a cool bonus not a deciding factor by any means.[/FONT]
[FONT=&quot]
There is also a Np242 Transfer case option that Has Full time 4wd option for the Street. [/FONT]
[FONT=&quot]
The Np231 T-case Is Part Time 4wd and Better suited to heavy Off-road use.
I use 4wd hi In slippery situations on road with my NP231 and it is fine so I don't feel like I am missing out not having Full time.

Reccomended reads for XJ info:[/FONT][FONT=&quot]
Before you buy[/FONT][FONT=&quot]
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/

After you buy
Check out the FAQ pages here,[/FONT][FONT=&quot][FONT=&quot] mainly in the second and third page.
[/FONT]http://www.naxja.org/forum/forumdisplay.php?f=165

Such as :

What axles do I have ? http://naxja.org/forum/showthread.php?t=101249

What transfer case do I have?: http://naxja.org/forum/showthread.php?t=101238

What transmission do I have ? http://naxja.org/forum/showthread.php?t=101120

Dana 30 info: http://naxja.org/forum/showthread.php?t=101343

Dana 30 Faq http://naxja.org/forum/showthread.php?t=101124

rear axle strength comparison http://naxja.org/forum/showthread.php?t=101345

Dirty method for measuring existing lift height http://naxja.org/forum/showthread.php?t=912893

After you buy your Xj[/FONT]
[FONT=&quot]When you start to modify check out other useful threads in the FAQ area such as.

Do I need my Sway Bars?
What is a SYE and when do I need one?
What gear ratio do I want ?
What would it take to have a front Dana 44?

There are walkthroughs in there as well Including Rear disk brake conversion (I love mine)

I have researched Every problem and Modification I have done to my Jeep by google searching any Xj Question I can think Of and adding Naxja behind it. [/FONT]
[FONT=&quot]You can site search but If you don’t it will focus on naxja but not completely ignore relevant threads from some of the other couple of Xj sites that have great info.

One Naxja tip is to scroll all the way down on the threads and look at the similar threads when you are close to finding what you are looking for.

Rule of Thumb Search First then Post![/FONT]

 

[joe_peters]

RENIX--Renault/Bendix XJs are 1987-1990.

Cherokee XJ years of production--1984 to 2001.

Bast*rd year--1996.

Can a well-cared for XJ last more than 300k miles? YES. Are there many (any) "well-cared for" XJs out there? NO.

The unibody is the CRITICAL part of the XJ--make sure it isn't rusted out/bent/fractured in areas that can't be easily reparied.

 

[bugout]

RENIX--Renault/Bendix XJs are 1987-1990.

Cherokee XJ years of production--1984 to 2001.

Bast*rd year--1996.

Can a well-cared for XJ last more than 300k miles? YES. Are there many (any) "well-cared for" XJs out there? NO.

The unibody is the CRITICAL part of the XJ--make sure it isn't rusted out/bent/fractured in areas that can't be easily reparied.

Please explain the "bast*rd year" comment? As I have a 96...

 

[Fore Wheeler]

Yep, the HO started in 91

 

[OutkastBoss]

Please explain the "bast*rd year" comment? As I have a 96...

I know when I was researching the 97 wiring revisions that can make SOME of those confusing to work on, some people were saying they thought it was the 96 that had those issues.

So maybe the 96-97 years would fall into that.

 

[8Mud]

Please explain the "bast*rd year" comment? As I have a 96...

They tend to produce the XJ's in a series and don't redesign them much between years in a certain series, usually a 3-4 year series before they do a major redesign. A series usually has more parts in common than they have different, usually.

The 96 seems to be an oddity, many of parts changed in the middle of the that year. Some changes were even progressive throughout the year, for instance if my parts guys are right, they changed the connector for the rear CAT 2 times. As far as I can tell I have a one off connector on my rear CAT, that matches no known 96 O2 sensor connector (but may be the same as a 95 front O2 connector).

The MAP is specific to that year as far as I know and works in no other year.

Jeep does a pretty good job of matching the parts to a specific XJ using the VIN number, the parts stores not so good, in my experience.

The list of oddities is long, gets complicated and confusing. Even finding an FSM (factory service manual) is rough. What the Jeep OEM parts catalogue says is the right part, may or may not be the right part depending on when the data was updated. My guess is an annex (or two) was added or the parts catalogue was amended, possibly multiple times.

Mine seems to be odder than even the odd 96, mine is an export model.

I'm usually best off removing the part that is bad and carrying it down to the parts store, which can save a lot of wasted trips. I've gotten pretty good with a vernier caliper to measure before I buy.

 

[Fore Wheeler]

...obd II started in 95 iirc

96 had a lot of year specific parts. It was the first year of pass airbag. Essentially a late model xj in an early body.

 

[bugout]

They tend to produce the XJ's in a series and don't redesign them much between years in a certain series, usually a 3-4 year series before they do a major redesign. A series usually has more parts in common than they have different, usually.

The 96 seems to be an oddity, many of parts changed in the middle of the that year. Some changes were even progressive throughout the year, for instance if my parts guys are right, they changed the connector for the rear CAT 2 times. As far as I can tell I have a one off connector on my rear CAT, that matches no known 96 O2 sensor connector (but may be the same as a 95 front O2 connector).

The MAP is specific to that year as far as I know and works in no other year.


Jeep does a pretty good job of matching the parts to a specific XJ using the VIN number, the parts stores not so good, in my experience.

The list of oddities is long, gets complicated and confusing. Even finding an FSM (factory service manual) is rough. What the Jeep OEM parts catalogue says is the right part, may or may not be the right part depending on when the data was updated. My guess is an annex (or two) was added or the parts catalogue was amended, possibly multiple times.

Mine seems to be odder than even the odd 96, mine is an export model.

I'm usually best off removing the part that is bad and carrying it down to the parts store, which can save a lot of wasted trips. I've gotten pretty good with a vernier caliper to measure before I buy.

...obd II started in 95 iirc

96 had a lot of year specific parts. It was the first year of pass airbag. Essentially a late model xj in an early body.

I always though there was somthing a little off. Everytime I've gone into the parts stores, I have to bring the part or a picture of a part....

 

[Digger87xj]

...obd II started in 95 iirc nope.

96 had a lot of year specific parts. It was the first year of pass airbag. Essentially a late model xj in an early body.

'96... another reason for the bassturd year

 

[sidewaysstarion]

'91-'93 Are apparently good years for renix Xjs.
With a closed cooling system, no vacuum disconnect front axle, improved power and electronics in the engine.

The 87-90 ECU is called "Renix", it does not store Codes you use a multi meter to read and diagnose.
Apparently easy to work on with a reputation for being the longest lasting XJ but they are older than dirt and people seem to spend a lot of time keeping them running due to failed sensors.

Wat... :wierd:

 

[OutkastBoss]

Wat... :wierd:

Nice catch that should have said non renix or most likely not referenced them at all since it is the begining of the H.O. , would go back and fix that if I could.

 

[Fore Wheeler]

Re: Re: XJNewb Crash Course

'96... another reason for the bassturd year

Yes, you are correct sir.

 

[Red91Laredo]

[FONT=&quot]
'91-'93 Are apparently good years for renix Xjs.
With a closed cooling system, no vacuum disconnect front axle, improved power and electronics in the engine.[/FONT]

As already stated '90 was the last Renix year, I'd tweak that statement to say '91-'96 are good years for the old body style, or '91-'95 if you want to avoid the '96 model year oddities.

I'm not exactly sure when the disconnect front axle ended but I believe it may have been used in some of the early '90's models, someone correct me if I'm wrong. My '91 has the non-disconnect axle since it came with a NP242, I've had a few people comment on how it would normally have the disconnect axle though.

...obd II started in 95 iirc

96 had a lot of year specific parts. It was the first year of pass airbag. Essentially a late model xj in an early body.

'96 XJ's had a passenger airbag? I didn't know they got one before the 1997 redesign. I know 1995 was the first year of the driver airbag.

I've heard that 1997 was a weird interim year where they were still using up some of the old parts. For example some '97's still have the old style door hinges though most got a redesigned version.

If I were buying an XJ, '91-'94 would be my pick for the old body style (only because I prefer the non-airbag steering wheel), and '98-'99 would be my preference for the new body. But I'd pick one based on condition rather than year because you can't really go wrong with any XJ solely based on what model year it is.