Project: Slippery Slope – a ’91 MJ runner

[Gjeep]

AI did a good job recreating the MJ...and toad.

[GonzoTheGreat]

This is awesome! I'm glad to see it moves under its own power again! Its a beautiful truck! 

[Smokeyyank]

Great work! Love what you did with it. 

[fiatslug87]

16 hours ago, 89 MJ said:

Like this? Sorry, I had to

 

Haha

[Gjeep]

Chief graphics in progress! I started laying these out wet with the eventual help of a heat gun in certain areas.

 

The passenger quarter of the bed is probably the most challenging panel on the truck because of the curve and all the body damage. The exhaust pipe had crinkled up the lower portion of the sheet metal. It was bent up pretty good and I straightened as best I could without refinishing. Also in general, the paint on this Comanche is far from perfect — when it was repainted they painted over scratches, dents, scrapes and the occasional spec of dirt. Love it. Trying to embrace the ‘beater is neater’ mantra…

 

 

 

Something I did around the graphics that the factory did not do on the MJ Chief (but did on the XJ Chief) was paint the lower rockers matte black to blend the graphics into. Looks better than seeing streaks of body color in areas where the graphic doesnt fully cover. Which is quite a bit.

 

 

I trimmed from some spare vinyl I ordered to get this to wrap right into the jamb area as it should. The graphics as they were didn’t have quite enough to make it happen.

 

 

Tomorrow morning I’ll install the upper thinner stripes above whats already laid out. Here’s how she currently stands…

 

[Gjeep]

Upper pinstripes in place, passenger side and tailgate done. A never to have existed ’91 Chief is born.

 

 

[89 MJ]

Looks great! I really like the wheel choice with the graphics. 

[fiatslug87]

14 hours ago, Gjeep said:

Trying to embrace the ‘beater is neater’ mantra…

If this is a beater mine are piles of crap.

 

Seriously, looking Great!

[eaglescout526]

Chrysler should’ve never discontinued the chief packages on either. Nothing says “I command the road and trails” like those graphics. 

[watchamakalit]

[Gjeep]

Refinished rear flare with NOS bumper end cap. The brackets holding the flare on are original to my ’92 MJ and I anti-seized the hell out of those studs before tightening down. Every single stud broke off this MJ’s original brackets when removed a year or so ago even though I soaked them.

 

 

NOS refinished front flare with Crown repop brackets.

 

 

It’ll be a couple weeks before I get the driver side and hood graphics on as I’m still finalizing changes to the Stroker Comanche’s graphics. This MJ is my test mule for those.

 

[NickyV]

On 12/5/2025 at 2:00 PM, Gjeep said:

RediRad is the aux unit I installed in my other Comanche that got me to BlueTooth.

 

 

I have already rigged up Bluetooth to my MJ. I'm pretty happy with the setup... but seeing as I often make "perfect the enemy of good," I'm still thinking about how I can improve my mod in the future.

 

This RediRad is really cool. I like how you get to assign an AM or FM frequency as the dedicated aux input! But since I went through the trouble to make myself a channel switch (one for the stock radio and one for Bluetooth), I don't think I'm going to swap out for the RediRad.

 

But that leads me to my question: Have you (or anyone else following this thread) found a suitable product that can do both Bluetooth music and handle hands-free phone calls? One of these days, I'd love to be able to be driving down the road, listening to my tunes and then be able to take a phone call. I wouldn't mind if I had to push a button or flip a switch to toggle between stereo and call. But I do want it to be relatively seamless.

 

And I also want to maintain my stock radio. Maybe one day I'll switch to one of those fancy "RetroSound" head units. But they are expensive and the closest model to what I'd want is the Grand Prix... And it isn't quite the right look in my opinion.

 

Anyway... has anyone been able to accomplish this in their MJ? 

[Gjeep]

This — and I bought it and installed it. I believe this is what you’re talking about. The BT reception radio quality wasn’t as good to me as RediRad and that was the priority. If Redi-Rad didn’t exist this would be my option.  

 

[NickyV]

Thanks. Yes. This is what I'm talking about. Thanks for the link.

[Gjeep]

Good chance this Jeep is getting an early birthday present. I have a lead on factory MJ 44 with low miles, 3.55 gears. If all works out will put 4.10's in it... and get a proper length driveshaft made. That will be an end of year project as I want to get the Stroker MJ done first. Lucky to find one.

[Gjeep]

At some point, this Dana 44 made it's way onto a ‘92 long bed 4.0L AX-15 4x4. The axle is a 1st gen MJ 44 having the separate breather line. And that breather line opening has a small plate welded over it I’ll be removing. The diff tag says it’s a 3.07 factory LSD axle, and although it’s not original to that truck it is correct for that trans (as the factory set things up). And u-bolt plates were also first gen but not 44 variants. Always an adventure hunting down a rare-ish bird... In the end I’ve got a 44 for this Chief clone. Guaranteed it will be 100% gone through towards the end of this year. Eaton locker with 4.10’s. Keeping the drum brakes this round.

 

[Gjeep]

I took a closer look at the breather line patch this morning and had a feeling I could pry the welded cover off as I didn’t see any prep done. But first I needed to remove the brake line... Done, no struggles. On to the breather line mess – I saw a lip in the patch and went for it, wedging a flat blade screwdriver in the spot and hammering away. Sure enough it came off with little effort or clean up. 10 swings at the most. Knocked right off. Neither were the fight I was expecting… It’s a good day.

 

 

 

[fiatslug87]

[Salvagedcircuit]

4 hours ago, Gjeep said:

I took a closer look at the breather line patch this morning and had a feeling I could pry the welded cover off as I didn’t see any prep done. But first I needed to remove the brake line... Done, no struggles. On to the breather line mess – I saw a lip in the patch and went for it, wedging a flat blade screwdriver in the spot and hammering away. Sure enough it came off with little effort or clean up. 10 swings at the most. Knocked right off. Neither were the fight I was expecting… It’s a good day.

Aww yeah! 

[Gjeep]

I peeled off the driver side graphics related to my other Comanche build and finished laying out the Chief graphics that go with this project build. Finito. (Photo a bit pixilated for some reason.) 

 

 

When I got to installing the new step bumper driver corner there was a noticeable (over 1/4”) wider gap body to corner on the passenger side. Since there’s no ability to adjust the bumper itself, I cheated. Added 1/4” thick stainless steel washers. When I did that, I needed to re-drill the bumper topside holes that retain the 2 bumper corner push pins. The gaps are the same now. Success.

 

 

 

[Gjeep]

Got around to cleaning up and painting the MJ-specific SnugTop I found a while back. Decided satin black was the way to go to keep the Chief graphics poppin'. Next up... rebuilding and gearing the D44.

 

[fiatslug87]

That looks great! Have you been driving it around?

[Gjeep]

She's my daily. 88K on the clock now. Bought it at 85K. 

[Gjeep]

It was time to free up some workspace around the old 4.0L… oil changes were unnecessarily difficult. Time to relocate the charcoal canister. In mid-1998 Jeep decided to move the XJ’s charcoal canister from the inner engine bay ‘frame rail’ (where our MJ’s is located) to just in front of the rear axle on the exterior floorboard driver side. Pure genius. All ‘98-‘01 XJ’s had this set up.

From the early Renix 4.0L days through 1997 the cylindrical charcoal canister was located way too close to the engine oil filter. As equipped from the factory Renix and early HO years weren’t too much of an issue as the oil filter was more or less vertical (spectacularly dumping oil out at every oil change). I’ve always converted early era MJ/XJ’s to the later horizonal oil filter setup for a somewhat less messy oil change. MJ/XJ AW4’s have the trans cooler lines running just below the oil filter in addition to AC lines (R134a ‘94.5-‘96 XJ setup as I’m running have lines wound in a bell shape for flow making the oil filter extremely difficult to loosen with a wrench/ eventually remove), spark plug wires, and heater core hoses (yes, I’m running ‘97+ XJ hoses) cluttering up the entirety of that area. I have barely 3/8” to maneuver the slip-around filter wrench into place. The original setup...

 

 

And below is the revised setup comprised of an ‘00 XJ canister bracket (installed with a new Standard Motors charcoal box), a cobbled/cut up hard vacuum line from the same wrecked XJ that runs along the frame rail to the firewall, two Renix era engine vacuum harness’ large rubber elbows (Crown Automotive new), the original ’91 MJ horizontal HVAC vacuum line cut and now running vertical from the bottom firewall up to the intake manifold rear-most port, and a ‘97+ XJ air box/ lid (at right in pic below). Other doo-dad’s include a new freshly bent 1/4” brake line taking whatever vapors that exit the two roll-over valves at the top of the MJ fuel tank into the charcoal canister and a ‘98-early ‘99 TJ canister breather ‘top hat’. (The TJ had an almost identical rectangular canister to the later era XJ with a different bracket. The difference TJ to XJ is that the ‘98 XJ instead of the ‘top hat’ ran this breather line up the frame rail up to the lower center area of the firewall where it just stopped and connected to absolutely nothing. ‘99+ XJ’s saw that breather line connected to an even more convoluted emissions venting system.) An alternative to this TJ cap would be a simple breather line into the MJ frame rail.

 

 

 

 

 

 

The end result is a ton of space around the oil filter. I can actually get a whole hand and arm in there. Perfecto. (Worth mentioning in this writeup, both my MJ’s are running an exhaust turn-down pipe just after the muffler. The exhaust doesn't go all the way back. But based on the trajectory of the muffler it looks like running this setup with the stock MJ exhaust wouldn’t be an issue.)

 

 

[JZLAJeep]

Impressive! And so clean!