aris_garage_builds

Been a while since I've been able to update this thread - life's been busy the last year (new job, weddings, travel, the usual time thieves haha). But I've been working on the Comanche during it all. I spent most of the past year slowly trying to debunk this clutch issue, with no real success. Sadly the 2.8/AX5 combo seems to be impossible to find parts for nowadays. Everything I've tried to order has not been compatible, despite being listed as the correct part. At this point, I just eager to be able to drive this thing and I have a spare 4.0 from an XJ sitting in my garage waiting to be swapped into something. The long term plan was always to 4.0 swap this rig, I just wanted to see if I could get the 2.8/AX5 going again first. I think I'm going to shift my focus to swapping the new engine so I can get it back on the road and have confidence I'll be able to find parts in the future since the 4.0 is a platform that has much wider support. Excited to get the MJ back on the road, seeing it sit this year had made me sad. So with that, I sent my 4.0l block and head off to the machine shop to get cleaned up. Got it hot tanked, decked, and bored 0.020. Also had them clean up the valve seats and install the cam bearings, since I don't have the proper tools for that. The block itself is from a 99 XJ (0630 head and the 53010449AA NVH block) I think it'll be a good base to start from. I'm planning on using a HO donor for the electrical / rest of the system, as I want to keep this build as OEM+ as possible and avoid the later OBDII items. I also found an AX-15 from a later model XJ with the external slave, so I snagged that for the MJ as well. Seller even included the whole clutch system (disc, pressure plate, flywheel, hydraulics, and 97+ pedals) with it, so this should be perfect for mating to the 4.0.

I'm currently refurbishing a 4.0 HO HVAC Box to swap into my MJ. Mine did not come with factory AC, so I'm planning on adding it while I already have the dash pulled apart for my 4.0 swap. Although I ran into a bit of a speed bump - while disassembling the HVAC box I broke the thermostat / probe that connected the the AC evaporator core. I'll include a picture below of the part. I've done some researching and it appears this part is no longer made / quite hard to find. Is there a good option for replacing it? If not is there a way to bypass it? Or possibly a way of upgrading to the 97+ AC core that doesn't have the probe? I'm using a 95 / HO wiring harness for the engine swap so would love to avoid OBDII parts if possible. Appreciate any advice, thanks!

I'm usually a red and black fan, but I gotta say on a MJ the chrome just looks right.

Located in a U Pull and Pay salvage yard in Denver. 86' Longbed, 2.8l V6 Manual 4WD. Red with burgundy interior. Tow Mirrors, Full Gauge Cluster and AMC 20 Rear Axle.

I grabbed the vin number, so I’ll plan to add it to the registry if it’s not already there.

I grabbed some trim pieces, tow mirror brackets, and the wear window seal. Other folks have shown up to start picking it apart, so I expect the rest will be gone shortly. I don’t have a burgundy interior, so if anyone needs these happy to sell them for what I paid for them.

I’m not sure I have a good way of transporting the axle otherwise I would have grabbed it haha, I’m in the daily today.

I believe it is

Located at Denver U Pull and Pay. I’m here now grabbing what I can if anyone needs anything. Bed is already gone and rear glass is broken.

https://www.facebook.com/marketplace/item/1150820850406089/?ref=saved&referral_code=null

Last I spoke with those customer service they were planning on only reviving it as a one-time group buy and not fully bringing it back to production. So I was pleasantly surprised when I saw it pop up again on the main store. With that in mind, I wouldn’t be surprised if they remove it again in the future. I’m definitely planning on grabbing one while I can! Mine has a FEY bumper the PO that is super dented and rusting out.

Not sure if this has been shared elsewhere, but JCR has brought back the DIY MJ Rear Bumper kit https://www.jcroffroad.com/product/DIY-MJ-R.html?_gl=1*yjn9kz*_up*MQ..*_ga*ODI5NjkwNS4xNzcwNTI5MDE4*_ga_KPFHN1JDCM*czE3NzA1MjkwMTgkbzEkZzEkdDE3NzA1MjkwMTgkajYwJGwwJGg1NjQ4NTU3MA..

Confirmed that the master isn’t leaking, it’s freshly replaced along with the slave. Also triple checked that the bolts were all torqued correctly before reinstalling the trans. I stuck a borescope through the starter hole after bleeding the slave and had a buddy press on the pedal - confirmed I could see the clutch fork moving, yet the clutch wouldn’t fully disengage. The clutch / pressure plate theory is intriguing. I did replace the pressure plate but it’s possible something is faulty with it or with a spring. I assume confirming this would require pulling the trans back out?

That was my initial thought as well - this is actually the second clutch disc I've tried during this repair When I pulled the transmission the first time, I put in a LUK clutch (part number Luk-01-024) and ran into similar symptoms. I pulled the transmission back out and compared the clutch disc with the original one that I pulled out of the truck - I quickly noticed that they weren't the same depth. So I ordered a second clutch from M-PACT (haven't used this brand before but the specifications seemed correct for the 2.8, so figured it was worth a shot). When the M-PACT arrived, I compared it with the original clutch and it looked identical. So I was hoping that would fix my problem. Now that the M-PACT is in the truck I'm getting the same symptoms as before - Truck shifts fine when turned off, but soggy pedal and won't go into gear when running. Since the pedal was soggy, I replaced the master and slave with no luck and assumed it might be a bleeding issue. And that brings us to the present haha. I'm running out of ideas honestly, so I appreciate the help!

Yes it shifts fine when the truck is off. Just won’t go into gear when I start the truck.

Alright, I’ve got a bit of a delayed update. I ordered the pivot point piece I was missing and hoped that might be the problem, however I still can’t get it to go into gear. I did another round of bleeding using a steering wheel puller to compress the slave (much less sketchy than using a c-clamp hahah). It appears I got all of the air out of the system and when I compressed the slave the pedal would firm up nicely…but when I reinstalled the slave into the transmission the pedal would go soft again and it wouldn’t shift. This has me worried it’s a larger problem with the clutch or trans - any suggestions on what to troubleshoot next?

I believe it is the same one - the listing is posted by the same person as the original posting. https://www.facebook.com/share/p/1NHiokqvy6/?mibextid=rS40aB7S9Ucbxw6v Could compare the VIN to be sure, it's listed in the registry here:

Amazing, thank you so much! I’ll shoot you a PM.

Did you grab that console by chance? If so I’d love to buy it off you if you’re willing to part with it. Looks like the same color as my 86’s interior.

Oh man, I wish I had seen this sooner! I might swing by tomorrow and see what’s left to pick through.

Ah I see, I bet that is exactly what is causing this problem! It looks like it this part: https://www.summitracing.com/parts/cwa-j3217479 I'll probably pull the system out and bench bleed it just to be safe (and ensure air isn't getting in somewhere) but given that the clutch won't fully disengage I think this is exactly what's needed. Thank you so much, I had no idea this little piece even existed!

Do you mean the rod / boot on the end? If so, yes. The only time I tried without it was when attempting the c-clamp / Haynes method (I removed the boot as directed to fully compress the rod). That seemed to be the most successful at moving air through the system, but I still couldn’t get the pedal to firm up.

Apologies for the delay, but wanted to follow up here! I ordered the McGard tailgate lock and it mostly fit. The lock itself fits perfectly behind the tailgate and tucks up nicely against the body when you close it. Included with the lock are two styles of cup like inserts that are molded to fit the hinges of modern popular tailgates. Unsurprisingly, neither of these fit the Comanche tailgate, but I put a little bit of foam in there as a temporary solution and that helped it stay snug. I think you could pretty easily 3D print a cup that was modeled to fit the MJ’s hinge. Might be a future project for me once I finish up some other repairs.

Anybody have tips on bleeding a super stubborn AX-5? I’ve been fighting a losing battle after replacing the clutch on my 86’ MJ (external slave). I bought it non-running and the master and slave cylinders were both bad. I replaced both and the clutch while I was at it (and got it running again in the process), but it won’t go into gear and the clutch is crazy soft. There seems to be air I just can't get out of the system. When I bleed, I get air bubbles coming out but can’t seem to build any kind of clutch pressure. I’ve tried literally everything I can think of - traditional bleeding method, power bleeder, vacuum bleeder, the c-clamp method that the Haynes manual recommends, but nothing seems to be cutting it. Is it worth pulling the whole thing out again and trying to bench bleed it? Willing to try just about anything at this point to get it driving again before the winter, I’ve never had a clutch give me this much trouble. Any other recommendations? Let me know if I can provide any additional info that would be helpful for troubleshooting, appreciate the help!

This is great to know, thanks all! I'll definitely pick of the Key Parts bumper kit. As far as tightening down the pivot point, I'm going to order this security lock. It should tighten things up and as an added bonus lock down the tailgate. Looks like the size is adjustable so I'm hopeful it will fit - I'll report back on how it goes in case anyone else is interested.