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Renix, pre-91 era XJ jeep tech differences

Ecomike

NAXJA# 2091
NAXJA Member
Location
MilkyWay Galaxy
If you still have an old Renix era XJ jeep, please post up and tell us what from a technical point of view what is different or special about yours from an OEM TECHNICAL perspective. I suggest we include the 84-90 XJs while the 87 was in fact the first Renix year. Tell us your Past or even current TECHNICAL service problems and how you solved them, if you solved them?
 
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One technical problem I had this week was finding out the hard way that the 94, 96 and 97 XJs have longer visors than my Renix era jeeps :( so to keep this technical they are about 4"s shorter on the older year jeeps and do seem to be swappable to the older ones. So I am stuck having them recovered at an upholstery shop, as I doubt there are any after market sources for new ones?
 
Nice post:rolleyes:
My XJ is titled as an 85. It started off life as a 2.5L because there wasn't a 4.0L available at that time. My wife bought it for me as a surprise birthday gift. In 86 they added throttle body injection, so I found a donor and moved all of that over. At the same time, I bored it .60 over and added a Mopar "purple" cam, along with Clifford Headers and 2.5" exhaust all the way back.

It had the AX5 manual tranny. While it had good power for rock crawling, and I had driven stick shifts for 30 years, it was a handful to keep it running over rocks sometime. I added an 11lb flywheel weight to increase the kenetic energy. You could pop the clutch on a hill and it wouldn't stall. It was fun to wheel but just didn't have the balls to pull the mountain passes here in Colorado at the 70 mph speed limit. It would hold 70 on the freeway but you might have to downshift every so often. I loved the 28 mpg.

Surprisingly, adding a snorkel gave it a ram air boost and added 5+ mph to my top end.

A couple of years later I got a spare 4.0L block and built one of the first 4.7L strokers in Colorado. The stroker now has over 200k miles on it. I will post later about what it took to mod the early 85 body to handle the 4.0L engine.
 
One technical problem I had this week was finding out the hard way that the 94, 96 and 97 XJs have longer visors than my Renix era jeeps :( so to keep this technical they are about 4"s shorter on the older year jeeps and do seem to be swappable to the older ones. So I am stuck having them recovered at an upholstery shop, as I doubt there are any after market sources for new ones?

I run across them every so often at the junk yards.
 
I run across them every so often at the junk yards.

The oldest one in my favorite jeep JY hunting ground is a 1994 now. They only had three HOs left, nothing older than 94 now :(

10 years ago they were only yard with in 15 miles of me that had any jeeps.
 
OEM technically speaking I have some welding to do on my 88. I was thinking about retiring it, but I actually prefer the lower torque curve of the Renix compared to my 96.

The HO may have a little better top end technically, but the extra horses don't really kick in until you hit the higher RPM band. Technically the HO should be a better quarter miler, but in fact is just about the same.

Just a technicality but the body and frame steel is better on the Renix era XJ, at least compared my 96.

Another technicality is my Renix will soon be ripe for Classic plates and registration. My road taxes and registration fees will all but disappear. It won't have to be smog tested anymore.

Technically, financially and practically it makes sense to hold onto it.

The technology may not be the best, but the Renix is reasonably reliable. Technologically it is still good enough.

I do have some technical work to do on my stereo and need to replace my speakers, so I can play my favorite tunes. https://www.youtube.com/watch?v=mP4CM3B5t3g
 
One reason I like my 1989 XJ is because it does not have those, (to me), stupid balloons like the way newer models. I find when I run into the occasional stump, or major rut not having a newer standard OEM, or connected balloon is very satisfying as I do not want one of those infernal balloons exploding and impacting my visual acuity lenses causing perhaps permanent eyeball damage, blah, blah. That, and I would not like to replace my old expensive to replace flight frame/glasses with 12kt gold filled eyeglass frames either. Perhaps such balloons are good around thousands, and thousands of other vehicles playing bumper cars.., but out here in the country there are other obstacle(s) more than likely hit at lower speeds, but also likely to have one explode in my face. Maybe a freeway mishap those things are life saving, but not in our back roads of mud, and snow, etc. Hence my RENIX does not have that feature thankfully. When I am on the highways around here, I consider every oncoming vehicle as someone out to kill me, i.e., they are drunk, or on their damned smart phones texting someone, or talking to someone, or otherwise not paying attention to driving safely, hence I really try to read their vehicle behavior, and am always looking for an out! IF I had a newer XJ, I'd most likely disable those wires with my Leatherman tool... I wonder how many non RENIX era owners have done just that.., to disable their XJ airbags!?! I really don't expect any of 'em to chime in, as delving into our classic era of XJs' are just too obsolete, but perhaps just out of some odd curiosity they might.., perhaps. Where I live there are no annual shop checks to see if we comply in order to be rewarded with an added approval sticker in the windshield.

One thing I do not like about my RENIX is that the headliner droops in the Alaskan summer heat. Well.., painting my roof flat black in order to obtain a tad bit of a few hours of solar winter heat does not help the long summer thing much. (lol).

If I want to add OEM upgrades to my rather stock XJ, such as different axles, brakes, master cylinder, wheel bearings, etc., and such, would those questions be better asked in the modified section, if I just use a newer generation of XJ OEM parts, or would that be considered modified enough to forgo being in the OEM section for those mods? I mean like in the modified section they often weld a whole lot of things, and switch axles, and armor, and honking steering boxes, et al. I am finding it hard to be in the OEM section where most XJ discussions have nothing in it for me. Hmmm... Whoa is me, whine, whine, whine.., sheesh.., get a freaking grip!!!!!
 
lol... lastara

Just a technicality but the body and frame steel is better on the Renix era XJ, at least compared my 96.

You have a source for this or just some personal experience?

umm oem renix fuel delivery/ECU are surprisingly self sufficient when comes to dealing with non OEM devil magic.

The OEM body maintains a dry/wind free environment well.
 
My '88 is a manual with an AX15 swapped in. When I had a high idle problem went looking for a replacement TPS. They show different for auto vs. manual. The manual version was harder to find and about twice the price. Finally found out that the less expensive TPS for an automatic actually has TWO plugs and will work with either an auto or manual.

Dub
 
lol... lastara



You have a source for this or just some personal experience?

Mopar was bragging about their new stamping process when they took over Jeep, something to do with using water. Supposed to make the steel harder.

My experience is the end product (like floor boards) comes out thinner in some places, thicker in others and generally a gauge or so thinner overall. My 88 floorboards outlasted my 96 floor boards by years. Identical climate, identical maintenance etc.

Some of it may be the coatings are different?

I have a pretty good feel for sheet metal, I've fabricated and welded tons of the stuff.

Some of the Renix body parts are thicker and softer than the Chrysler pieces. Like I said, more a feel and experience type thing. I could measure and validate my feelings, but at least on the specific XJ's I've welded on it *feels* to prove true.

Jeez now I'm gonna have to tell my six kids I'm gay. LOL
 
lol... lastara



You have a source for this or just some personal experience?

.........dealing with non OEM devil magic.

What prey-tell is OEM devil magic? Does it have anything to do with RENIX cloaked electrical Gremlins or morphodite electrons?

The Renix era jeep bodies were hot dip galvanized, Lee Iaccoca came up with the idea for all Chrysler rigs when he took over Chrysler and the Renix jeeps after he bought AMC (and maybe before?) were hot dip galvanized, and mine are still rust free.. at some point in time the cheap electrophoritic black coating replaced it and rust was again Detroit's best friend, "planned obsolescence" as described by Delorean in his book "On a Clear Day You can see Detroit"....which he hated.

That is one of the reasons these old RENIX jeeps have outlasted every other vehicle older than about 1996-2000 now.
 
My '88 is a manual with an AX15 swapped in. When I had a high idle problem went looking for a replacement TPS. They show different for auto vs. manual. The manual version was harder to find and about twice the price. Finally found out that the less expensive TPS for an automatic actually has TWO plugs and will work with either an auto or manual.

Dub

High Dubster, nice to see you posting here, and to see another 28 year old OEM beast (the jeep not you, LOL) hanging in there with such great TECHNICAL expertise (you) working to keep her alive and kicking. When I started this second generation :guitar: OEM Tech thread here I was beginning to think I had 1/3 of the remaining working Renix jeeps on the road from the lack of post discussions here the last year or so about OEM RENIX jeep Tech.
 
Gay or Grey? LOL

BTW I think some one recently corrected me that our RENIX OEM jeeps were not hot dip galvanized (something I recall from Chrysler-Lee Iaccoca ads on TV) and they said it was actually zinc electroplated which makes sense. Might have been Cruiser54? Sad they killed Saturn at GM in 2009, as my daughter's 2001 Saturn (that competes for Facebook time with her RENIX 89 2wd beast that has been totaled per the insurance companies twice, and rebuilt three times by her and me), TECHNICALLY speaking has zero rust on the plastic-rubber body parts like doors...
I had some OEM compatible brake fluid leak on the under parts of the 87 RENIX Wagoneer last month and It stripped the OEM paint exposing the zinc coating/primer underneath.

lol... lastara



You have a source for this or just some personal experience?

Mopar was bragging about their new stamping process when they took over Jeep, something to do with using water. Supposed to make the steel harder.

My experience is the end product (like floor boards) comes out thinner in some places, thicker in others and generally a gauge or so thinner overall. My 88 floorboards outlasted my 96 floor boards by years. Identical climate, identical maintenance etc.

Some of it may be the coatings are different?

I have a pretty good feel for sheet metal, I've fabricated and welded tons of the stuff.

Some of the Renix body parts are thicker and softer than the Chrysler pieces. Like I said, more a feel and experience type thing. I could measure and validate my feelings, but at least on the specific XJ's I've welded on it *feels* to prove true.

Jeez now I'm gonna have to tell my six kids I'm gay. LOL
 
The BEST thing about a Renix in CA is the fact that there is no CEL for smog purposes.

I will agree it is one of the best things about RENIX jeeps, as anything older than 1996, OBD-II is 1996 and newer, is now Emissions testing exempt in Texas as well. The technical aspect is that the EPA decided there were too few vehicles left older than 1996 of any kind on the roads to force the stations to buy and maintain the dyno testers anymore as everything 1996 and newer is tested at the OBD-II computer and verified by the OBD-II port now. Glad to hear one more REnix 1990 jeep is alive and well as well as its owner/caretaker :)
 
The oldest one in my favorite jeep JY hunting ground is a 1994 now. They only had three HOs left, nothing older than 94 now :(

10 years ago they were only yard with in 15 miles of me that had any jeeps.


None of the JY around me have anything older than 93 it seems, plenty of 97 up. Either rusted out or crushed decades ago. Last 86 I saw was a wagoneer in 2004.

I didn't know that about the sun visors. Just picked up a set for my 85 never thought to check them.
 
None of the JY around me have anything older than 93 it seems, plenty of 97 up. Either rusted out or crushed decades ago. Last 86 I saw was a wagoneer in 2004.

I didn't know that about the sun visors. Just picked up a set for my 85 never thought to check them.

That was the mistake I made on the OEM XJ jeep visors too, never dawned on me that the 90/91 year was a switch in length that made the new OEM visors unusable on the 90 and older jeeps. I suspect it was a complete change over in 91 on the visors as the 94 and 96 and 97 I checked were all way longer that the pre 91 visors. That means we are stuck paying for or learning how to repair our old visors as the fabric and cardboard rots.:bawl:
 
Fabric on the 91-92 shredded in to almost nothing. The boys when toddlers kept sitting up front when it's parked and played the tattered visors into oblivion.
I might have lucked out on the visors because I was matching interior colors, pretty sure they stop red before 1991.

On the 1991 up I think they changed for the overhead consoles.


Sent from my iPhone using Tapatalk
 
This thread has some value, too bad the personal BS has to get involved. Let's keep it on track and move on with life. This is just the internet folks.

Thanks Bryan, with any luck this will get back to normal now.
 
My '90 XJ is pretty much amazing. Everything works and while it doesn't need emissions testing anymore (Texas), it passed with flying colors when I last took it in 2 years ago. The non-OEM stuff is the usual:

1) changed the coolant bottle and added an inline filler cap to rid myself of the PITA leaking bottle
2) upgraded the entire AC system to R134 out of a '95
3) changed all the rear glass to factory tinted glass I got from a wrecker on one of their 1/2 price long weekend specials
4) changed to beefier springs and shocks to get a little height
5) completed many of the "fixes" outlined in this forum including ground updates, headlight relays and door lock relays
6) changed all the locks to the single key version found on the '93 and up
7) removed the factory keyless entry and added a 3rd party device
8) re-purposed the (semi-useless) garage door opener hatch in the overhead and mounted a video screen for the rear passengers + added a dash mounted video and a rear view camera
9) replaced the power brake booster and Master with one out of a Grand Cherokee
10) changed the rear lights to the slotted design (removes the bottom bolt) used in the '93 for easier access

Lots more "little jobs" including repainting the whole thing (looks great) and refreshing the interior (dying the carpets, painting some of the plastic panels).

WRT the metal, my '93 (bought new) came with the zinc coating and a "lifetime limited warranty" which didn't amount to crap when the Chrysler refused to honor it when actual rust occurred (floor and one of the doors). Conversely, my '90 had only a small bit of surface rust on the roof where the paint had baked off and I had to weld a small patch on the rear quarter where the PO had removed the plastic plugs and then drove it through wet sand which collected inside the space behind the rear wheel. To be fair, the '93 lived a hard northern life while the '90 was a Texas truck from day one but I don't place a lot of stock in the Chrysler plating process and if I had to pick between the two bodies, i would go with the '90 every day of the week.

On a recent drive between Houston and Austin (140 miles), I used a little less than a quarter tank of gas which equates to close to 30mpg.

One of the nicest things about the '90 is the interchangeability with newer parts (like the AC, brake booster, glass....)
 
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