What year XJ to buy?

Hey folks... I've owned several XJ's before. I had a 93 that was lifted 4" and used heavily off road. It's been a few years since I sold it and now I'm looking to buy another XJ. This one won't be for off road use though. So, I have a few questions... basically things I can't remember.

First, generally what years would you guys recommend.
I want an auto, and was wondering when they stopped using the AW4, and was the tranny that followed as good as the AW4 was? Also, were there any years to avoid? Was oil blow by, or TPS and NSS issues more severe in certain years?

I drive alot for work, so gas mileage is another consideration...

Thanks in advance

knottshawk said:

Hey folks... I've owned several XJ's before. I had a 93 that was lifted 4" and used heavily off road. It's been a few years since I sold it and now I'm looking to buy another XJ. This one won't be for off road use though. So, I have a few questions... basically things I can't remember.

First, generally what years would you guys recommend.
I want an auto, and was wondering when they stopped using the AW4, and was the tranny that followed as good as the AW4 was? Also, were there any years to avoid? Was oil blow by, or TPS and NSS issues more severe in certain years?

I drive alot for work, so gas mileage is another consideration...

Thanks in advance

Click to expand...

They never stopped using the AW4
99-00's have head cracking problems, I think that's the years.
4.0 is a 4.0, aside from the intakes and heads no major changes to the block. There was a stiffener added to reduce NVH by chrysler, not sure of the time frame for that.
Electronics changed in 96 I believe to OBD-II

4.0 is 4.0? What about the HO vs. non-HO? What is OBD-II? Is it better or worse than before? Were there any TSB's about the head cracking issue you mentioned?

So the AW4 was always used in the XJ?

Aw4 was used as long as the 4.0 The Non HO (more oftan known as RENIX was used from 87-90. OBDII stands for OnBoard Diagnostics II (that's what all new cars today use and basically it means that newer scan tools can plug in and get any error codes from the computer, thus helping to diagnose a problem)

knottshawk said:

What is OBD-II? Is it better or worse than before?

Click to expand...

OBD-II (On Board Diagnostics 2) was introduced to replace the earlier RENIX (a collaberation of Renault and Bendix) system of engine management. Without an OBD-II code scanner, many beleive the earlier RENIX system easier to diagnose and maintain.

you then said:

Were there any TSB's about the head cracking issue you mentioned?

Click to expand...

As far as I know, ChyCo has never released a Service Bulletin nor even admitted to a design flaw in that particular head casting. Keep in mind that this issue is restricted to a relatively small number of Cherokees. A search here will reveal the casting number.

and finally you said:

So the AW4 was always used in the XJ?

Click to expand...

In all 6 cyl. Cherokees, yes. From '92 to '96 the 30RH three-speed was used in 2.5L, 4 cyl. Cherokees.

Dave

The "4.0" refers to the size of the motor (aka 4.0L). I believe the HO was introduced in 96?(correct me if i'm wrong). The introduction of the HO brought more tourqe and horsepower numbers to the 4.0. OBD II is the diagnostic system found in 96+ vehicles. Personally, I think its better to have OBD II than other computer systems...theres more software and more tools out today to diagnose problems with OBD II than in previous systems. If your looking for something as a daily driver but still want to have some fun on the weekends then I would recommend a 97+, they have a more modern feel to them. If your gonna be spending more time on the trails then a 96 may be the way to go, that way you get the OBD II and the HO.





Just my .02$ though....

HO was pre-96... Early 90's... I know some people liked the non-HO because it was supposed to have better low rpm torque.... Thanks for the input guys...

One more question... Did DC ever deal with the inadequate cooling system in the XJ? My 93 cooled terrible... I know it was common to get the GDI 3-core radiator, and that helped, but did they ever do any factory upgrades?

Renix was on the 4.0 up until '90. '91 and up are considered HO. The emissions controls instituted in '91, I believe, would be OBD I, although if you compare all the under-hood plumbing with an automobile of the same era, the Jeep has much less. They were considered 'light trucks' by the EPA, and as such were held to a lower standard than passenger cars. When the "96 model year rolled around, it was probably easier to apply the OBD II standards to all vehicles, as it standardized most diagnostic tools. I have an Actron scanner, and I wish it would be of use on our '92 and '95 XJs. I originally bought it for use on our '98 ZJ, but that lemon is long gone. I recently looked at a '86 with a V-6, and after one look under the hood, all I can say is I'm glad mine are newer. What year is best? I'm gonna say '94; old floor pan, no air-bag, non OBD II, but may have R-134 A/C. What I have found through the time I've been playing with XJs is that the hot running may be the build-up of crud in the coolant passage at the rear of the head, in addition to needing a bigger radiator. Mine was like that, and I know of others who have found the same thing. Not that these vehicles have a lot of design flaws, it's just that most other vehicles as old, with as many hard earned miles as our XJs have long since shuffled off to the crusher. Just a few thoughts...Ray

Thanks Ray,
I recall a jeep mechanic talking about using his steamer to cleanout the passages on the 4.0 and getting all kinds of junk out of it. That's probably a good thing to check if I overheat. I appreciate all the input you guys have given... it's been very helpful in refreshing my memory!

I own 4, 00', 96', 95', 90'. But the 96' is my favorite for no particular reason.

go renix or go home

buy a 2003

For safety reasons i got a 99.---Air bags---both sides.

my '93 with HO 4.0 makes me pretty happy.. no problems to report, other than the common high crank pressure (needs a rebuild on the top end IMHO, rings and such..)