brucecooner

This was something I was curious about, the lack of a true neutral in some 231's. I don't plan to ever tow it, but it may have other plans. I'm going to call Novak and ask about a stem to stern solution next week, and was going to see if their cases included true neutral. I am definitely in the "keep it as simple as possible" category. Something else I've wondered about is deleting the CAD for now, then later on getting a little bit beefier front axle with locker functionality and locking hubs. But I've read that locking hubs come with their own set of problems, and some are actually less durable because the innards are more exposed to the environment.

I read this just today on the Novak site... "The standard duty OEM 231 transfer cases are capable of transferring from 1600 to 1900 ft. lbs of torque (as claimed by NVG - actual experience puts this number quite a bit higher)." I don't think my motor is going to put out anywhere near those numbers anytime soon. Speaking of Novak, I called them today to inquire about a rebuilt 231, and he said the input side should be the short option for an AX, but that it was pretty forgiving, the output shaft is long enough to work with a range of cases. And they can get me a completely, and I mean completely, refurbished 231 for not much more than I'm out getting it from the builder, considering my options here...

Well it's nearly unanimous, it can be deleted without negative effects. Which leads to my next question. I was checking out my TC the other day and noticed the red and yellow lines are broken right at the TC. It looks like the other two have been fixed for a break in the same spot, where the lines turn to head to the front of the truck. So at minimum that's a vacuum leak right there (I think red goes to the intake?) Is the four line vacuum manifold-plug on the transfer case JUST related to working the CAD? I assume with CAD deleted I can plug those lines at the TC? Or is there an aftermarket plug to just replace that bit on the TC? And on that topic, does anyone know where on the intake manifold the line-to-TC plugs in? I'd like to just plug it at the manifold and remove the lines if that's an option with the CAD on all the time.

Ah, good to know. While cleaning the throttle body I did remove the old IAC to spray some fuel system cleaner in, and a lot of black buildup came out. But that didn't fix the high idle, hence its replacement.

I'm curious what, exactly, the CAD keeps from spinning. I know it disconnects the passenger side front wheel. Does that mean your diff is still spinning with the left front wheel? Or is it just the leftmost spider(?) gear in the diff that spins with the left front wheel? Or is the diff completely static when the CAD is disengaged? Anyway, curiosity aside I'm not really fond of things actuated by vacuum lines that have to stay soft and pliable and puncture free to work. I know there are aftermarket solutions that replace the vacuum actuation with a cable to the CAD. The thought of having a more physical connection from my hand to the part I want to move appeals to me. Then, there are those guys who just lock it closed and go about their business. Supposedly the CAD increases mileage, and I do plan to put some highway miles on this guy, so I might prefer to keep the CAD but upgrade the actuation. I've wondered if it's possible to replace the passenger side axle with a solid shaft. It seems that would be more trustworthy against breakage than a collar connecting two shafts. Also, the dash light. Does that light only tell you that the CAD is engaged? Or do the lights give you actual feedback on the state of the transfer case? (I'd assume the shifter would be your best bet on that). I'm not too worried about the dash light not being accurate, UNLESS it's critical for knowing what state the system is in, so you don't do something dumb like go down the highway in 4H. So I'm curious to know what experiences others have had with various solutions. Do you see a noticeable reduction in vibration or mileage with the CAD engaged all the time? Are those wire actuators a good idea? Or do they have some peculiar quirk that makes them more annoying than vacuum lines? Is it possible to have the dash light work with a wire based system?

Is "ISA" the same as the "IAC" (Idle Air Control) ? I was getting those random 3000+ idle starts last summer, and replaced my IAC with one from Napa (set as per the included instructions). I would still get the high idle occasionally. Then the high idle issue disappeared last fall and I haven't seen it since, but I'm wondering if it's a warm weather behavior. If we're talking about the same thing, I'd love to have the test steps so if I see it again I can test my valve. I'll definitely get a Crown one if that's the issue.

I'm on the hunt. You'd think a city the size of Phoenix would have a few old 231's for sale but no luck yet. ebay's always a possibility I guess. I do have some rando questions though. I'm looking at this one: https://www.ebay.com/itm/126324479362?itmmeta=01HQ7HGHQ1HFEF6TKCKNGDHRP4&hash=item1d69869582:g:rr8AAOSwi9xlxoGr&itmprp=enc%3AAQAIAAAA0HzP%2FqzUPm%2BfBXCWCxdA60XO9cOCCWNmijd1Q4XppxL04%2B%2BuI1dO2WvPQTEUr2oZ8167EZpJYP%2BG%2FeZKyCrmXPheq3A3chpRxdDph%2F82pICCMPGsJTckunponoxiGf%2FVI07581fFZdjT22t5j0GDOWD1XaXmc8ArL0l3ZPF940zVT6eV5jfEFPHHCvNPRLvjYnGg0Pf4N53VhLWTSP4RjVBh0gJcx890W77EeoteGGujG1FbcITjO8xUZn9TxBa2pZDisPDfZKPTZ%2BWCs061JJI%3D|tkp%3ABk9SR9CbwvG5Yw The listing says "Automatic" in the title. I haven't seen any indications that the manual/standard transmissions led to any differences in the TC. I assume all 231's will have the exact same bolt pattern, and I don't even have to think about manual versus standard sourced cases. I've seen "short input" on some listings. I assume that's something on the input side, is there anything I should be aware of there? My output side is definitely NOT the accordion style, which I see on a bunch of listings for later tc's. I took a picture of my tail shaft today. Part of me wants to say that tail housing is longer than the one in the ebay listing, but I really don't think that is possible. Or did tail shafts vary from year to year? But yeah, thinking that may be my next tcase...

I got a recommendation from the local speed shop for a transmission shop today, and they pointed me to a guy I've already been recommended to by someone else, so I gave him a call. Unfortunately he doesn't do installs, he's just a builder, but he's done lots of builds for the AX swap and for what I'm doing he highly recommended keeping the 231. Which is fine. I haven't heard anyone disparage the 231, I'm going to baby this thing no matter where I go, without a lift I can't take it anywhere extreme anyway, and I'll save some dollars for that future lift (or maybe someday I'll just get a TJ for wheeling *GASP*). On the upside, he can provide a rebuilt AX without a core for a reasonable price (cheaper than the online suppliers I've seen) and he's not far down the road so no shipping. He'll rebuild a 231 with the new input for installing at the same time, and this is where it gets interesting. My plan has been to source another 231 to attach to the AX, because I can't disable my Jeep for however long this takes. But this guy said I have to be very particular about the 231 I get. It has to be clocked for an XJ (or I guess I get an adapter ring), but it has to have the same speedo, linkage, and actuator mechanisms. I did plan on updating the linkage though. He said to get the assembly number off of mine and go by that. I looked at the tag on mine and found 89530 04301 So I've got some kind of plan, but now I'm wondering where and how I get the exact case I need. ebay has a lot of listings, but they are literally ALL for Wranglers. I guess I'm down to checking the for sale forums, and snooping for Cherokees at the u-pull-it.

I don't plan on doing any rock crawling, mostly just bumpy rough trails. A super low crawl would be nice but without any lift (yet), I can't go anywhere extreme anyway. Everything I've read indicates the 231 is a medium duty case plenty suitable for bumpy wheeling. This Jeep already has a Dana 44 in the rear with limited slip, which I hope makes a pretty good setup with the 231. The seller said the case is from a TJ, I don't know if their speed sensors were geared or electronic. He said it is from a TJ. Aw man, not much is fun to do under the truck. I've seen a video where a guy had to drill his AX for a Cherokee, but he was able to level it on a bench. When you said it requires body mods, did you mean only if the clocking is wrong? Or is the Rubicon case just too darn big even with the correct angle? I believe the product page at Novak said you can request an XJ clocking on a new transmission and they will do it for you, which is my best hope. Apparently you can get a jig that goes over the spline and uses the existing (Wrangler) hole for registration, with another hole off by 10(?) degrees to tell you where to drill for the XJ. The guy selling the Rubicon transfer case said something that shocked me though. He said the AX swap would require new driveshafts. But I've read plenty that says even though AX is about 1/4 inch longer, this will be taken up by the slip yoke on the back of the 231 (unless you want to go with SYE and driveshaft mods). Can anyone speak to that? Am I really looking at new driveshafts here? Because if so I might as well set up for a future lift.

Mostly, I'm just happy I can use braided line with whatever kit I get. More questions though... I've got a lead on a Rubicon transfer case. This sounds appealing because it looks like AX-15's are by default drilled for Wrangler applications, also the tc would already have a 23-spline input. From what I gather a Rubicon case should be a straightforward installation onto the transmission. I certainly wouldn't mind the lower ratio, AZ mountains can get pretty steep, and having what is apparently a stronger case would be a bonus. I don't care if it's overkill, if it's easy. I wouldn't mind if this requires a linkage change, I already plan on getting rid of the old stock linkage anyway, apparently there are some much better aftermarket designs. BUT apparently the Rubicon cases are larger than the 231. Would this mount and fit under an MJ/XJ, or would it require mount and/or body adjustment? Also, I'd have to wonder about effects on the output side. Would a Rubicon TC require driveshaft modification?

Good to know. I see Novak sells a bellhousing that's been cleaned and inspected. It's a later one so it meets the two main criteria: -CPS placement -accepts external cylinder https://www.novak-adapt.com/catalog/adapters/engine-to-transmission/amc/ax15-to-nv3550-amc/ Pricey though! I'm not too worried about cost here, I've bought very few large things I want in life (family always came first), but I saved some money that way, and this Jeep is really the first truly big purchase I've ever made specifically for ME. That said, why spend hundreds you don't have to? I plan to hit up the local-ish guy cruiser recommended. His shop is closed but he said he's got some parts lying around. The slave cylinder is another major area of inquiry for me. I definitely want to go external (hence the bellhousing requirement). Personally I would call increased pedal force an improvement. The master cylinder on my Jeep is fairly new, maybe a couple of years old. I think the internal cylinder is leaking, again, as I type this. But as I said previously, it looks like there's rust in the old line that got reused, and I wasn't very impressed with the master cylinder that was installed, it's got rust spots all over it already. I've been intrigued by those pre-built clutch line kits, where the cylinders are already attached with a braided stainless line and no bleeding is necessary, you just have to run the line down to the transmission (using curse words and magic, I presume). I was thinking last night about acquiring the parts, assembling what I can, and seeing if an area shop can just install what I take them. Then the job is more of a straightforward install, which more shops might be willing to do. A risky plan, but if I were risk averse I wouldn't own a 40 year old truck (that said, it seems some four year old trucks are a bigger risk than this one). And if a shop won't do it, I'll just have to go with what I got. I also plan to get another NP231, rebuild it if needed, and install the new input hub, so I don't have to take my Jeep out of service while I work. Then I'll just have a spare tc on the parts pile. What is everyone's opinion on the "adapter" mounts, that supposedly let the AX15 use the existing crossmember? https://www.novak-adapt.com/catalog/rear-mounts/rmax15-rear-mount

So an external slave cylinder swap turned into a new transmission. Dang. But I think the real hero of the video is the patio heater, I hate the cold too. I liked and subscribed though, good stuff. I wonder if I'll get an AX drilled for a Wrangler too... I tried the freedom email and he actually got back to me. Unfortunately he closed up shop start of this year, so I just missed him. He gave me a couple of leads though, and said he still has parts for sale, so I might be hitting him up for stuff. I watched a video earlier today by a shop selling an adapter that bolts to the AX15 and to the original crossmember, which intrigues me. Some more questions I've found... I've heard the AX is about an eighth of an inch longer than the BA. Supposedly a slip yoke will take this up, and supposedly all Jeeps had a slip yoke at the rear. I'm too much of a noob to have known to check for this, but I could swear I haven't seen a slip yoke on mine (will check tomorrow). DID all Jeeps have slip yokes? So apparently I'll have to get a bell housing that accepts an external slave cylinder. And I've read that all models after '94(?) had an external slave cylinder? But would those all have the spot for the CPS? So, what's the process for choosing a bell housing? I assume the bolt patterns are the same front and back regardless (4.0 to AX15). Is someone making brand new bell housings for this application? (I guess Advanced Adapter would be the goto for that) Is the bolt pattern at the back, to the TC, going to be the same regardless of the transmission? I did see a video where someone pointed out the BA only used 5 bolts, so they put a plastic plug in the sixth hole in the TC, and that hole had to be tapped before use.

If I were just driving it around town, I wouldn't worry about replacing it. I can live with the cranky shifts till it warms up. But I made the mistake of having the fluid changed a while back and now it's leaking from every seal, dangit. I found that company's page, but looks like they may be out of business. I am hunting around for options. Yeah I was mistaken on the transfer case. It looks like I can get the transmission and parts for a swap that comes with the new 231 input from advance: https://www.advanceadapters.com/4407 That plus the crossmember, mount, and I'll do the external cylinder swap, oh and rebuild the 231 since it's gotta be opened anyway. I'm sure there are lots of other bits I don't even know I need... I need to watch a video and see exactly how far beyond my abilities this job is. My main fears are being able to get to all the bell housing bolts, not gimping up the CPS, and I understand there's some tweaky alignment stuff somewhere in the whole deal. I think it'll require running new hydraulics for the clutch too. The current clutch was replaced not that long ago but when I check the reservoir, it looks like there's rust in the fluid so the old line should probably get replaced. But after bending twisting and installing almost every foot of brake line on the thing last year, I have PTSD from the thought of running more solid lines.

The Peugot's second gear synchros have been particularly obstinate this winter. I don't think I'd trust its internals to lug me up a mountain anyway. So I'm looking for information and recommendations on what sort of manual to manual swaps are available. I want to do some offroading, have the ability to travel some genuine 4x4 trails, but I'm not going rockcrawling. I'd like to have some towing ability, nothing large, but that's not a hard requirement. The AX15 has a good reputation, but it's a different length, and apparently you need to replace everything out to the diffs if you go that route. The later NV3550 might still work with the 231 transfer case? Can anyone speak to the pros/cons of some different choices? Which ones might be easier to source? Which ones will have the kits and adapters to get the job done? One big wrinkle I bet is fun to deal with is that the CPS is stuck up on the bell housing. Being manual already, I don't think the engine will care what it turns, but I'm no mechanic. And then I'm sure there are 1000's of little details I'm not even aware of. I know it can be done in a driveway but if I'm being honest, I don't have the skills to align the things to the other things. But, I saved a LOT of money by not buying a new Gladiator, so I can probably afford having it done. IF there's a shop on earth that even does things like this that is.

Thanks, I'll take a look. I forgot to mention it in my post but I did change the oil after I put on the new regulator, figuring the current oil contained more gas than spec called for, so there's a chance I just didn't snug up the new filter well enough too. Will be poking around that side when the weather allows.

It took me long enough (life's been crazy lately) but I can finally report that a new fuel pressure regulator seems to have fixed the problem. I put a new unit on about three weeks ago, but didn't have the chance to really get out in the Jeep until this weekend. Whenever I got in it yesterday and turned the key, it would start. It doesn't start fast, it takes it a few turns to get going, but based on all the videos I've watched where somebody starts an old 4.0 that's par for the course. Apparently deleting my "7th injector" was the cure. Warning to anyone undertaking this, the new unit's vacuum line input might be a different size than the old elbow. I just cut a short length of quarter inch silicone tube I had lying around and that made for a snug fit. Also, the little nuts and bolts (T25) that hold the regulator's bracket to the rail are not the easiest to get to. I removed that bracket to the right that carries the CCV tube (and others), and disconnected injector #1 and moved everything back as far as I could and it was still a finger ballet to get the little bolts back in the bracket. I highly recommend putting tape or paper towels under the regulator area or else you will lose bits to the depths (there's a T25 bit that lives somewhere under my intake manifold now). So a big huge thanks to Omega-hm (how does he type that?) for pointing me to the FPR And thanks to everyone else who's been along on this thread. I am sorry to say that this did NOT fix the surging idle. I'll have to continue on with cruiser's tips. Of course I was immediately punished for fixing this issue with the development of a fat new oil seep, coming down the passenger side of the pan from...somewhere. I snugged a few pan bolts but that wasn't it. But I didn't name this thing the Heartbreaker for nothing lol.

I'll definitely make an update if I learn anything about the idle. Today I finally got a chance to debug the Jeep again. I've searched a lot of threads on hard crank, and the only one I've found that matches my motor and situation exactly was due to leaky injectors. I trust the source of my rebuilt injectors, but he could have just rebuilt a set with some worn out ones that leak. However, if it's leaky injectors, I had the revelation that I can just REMOVE heat from the equation. So I turned the key and pressurized the rail, then turned the key off and walked away. In about half an hour it started, pretty much okay but a little slower than a cold start. This start re-pressurized the rail, so I gave it another half hour or so. The next start took several revolutions, and it ran rough for a few revolutions after. Mind you, it was a cool day and the engine is in the shade of the hood, everything was cool to the touch all day. This is NOT a heat soak situation. Another half hour, another start, and it was getting really difficult. My son watched was behind it and said the tailpipe was putting out some white smoke. Hmm.... I waited again and had my son start it while I watched the tailpipe, and it was giving off a good bit of white smoke. So I was all ready to blame the injectors, BUT I remembered Ohm's note about the FPR. I pulled the line from the regulator to the intake manifold and gas came out. I'm pretty sure it's not supposed to do that, is it? So at this point I'm pretty suspicious of the regulator. With that line pulled, the rail was still holding pressure, mostly. It does do down slowly over about 10 minutes or so. I had to button everything up at this point, but since then I've had the thought I should pressurize the rail and then pull the FPR line so that it CAN'T leak back into the intake manifold, and see if that changes my result. Then I should know it's the FPR for sure. At any rate, it seems to need a new regulator for sure.

I did suspect leaky injectors when I first started looking into this, and replaced the originals with a set of rebuilt 4-hole injectors. The old ones were very dirty. I will try the WOT trick next time I'm messing with it though. I have one of the lights that you put in a plug wire to check for spark, I need to dig it out and start checking that all the cylinders are firing.

Been a while since I've had the time or health to fiddle with the Jeep, but it's still giving me the hard start when warm. I'll drive it for short hops where I know I can jump back in it right away, but if I part it at a store or anywhere for a while, sometimes it will darn near not want to start. I got a fuel pressure gauge for the rail recently to see if it really is the fuel pump, and I think I've ruled out a fuel issue. At a cold start the rail goes right up to 30-ish pounds as soon as you turn the key. I drove it a couple dozen miles the other day and parked it in the driveway. Immediately put on the gauge and it pressurized soon as soon as the key was on. It started right away. I went out maybe ten minutes or so later, and again it pressurized and started pretty quick. I went out about twenty or thirty minutes later, and although the pump was still pressurizing the rail, it would crank but didn't want to start. So I don't think it's anything with fuel delivery, maybe something with spark. Is it a useful clue that it has to sit for a while before I get the hard start? I would have thought after a long drive everything would be good and hot, but it had to sit there a while before the hard start. I have noticed that right after it does have a sluggish start, it misses a few times before settling in, so maybe spark is the issue. I would think I could rule out the distributor, being right next to the engine it's surely good and hot all the time. Anyway, has anyone ever seen a Renix that has to sit up a while to get heat soaked? That would seem to point to something farther away from the engine, I think. I've done the grounds on the block and the block to firewall (a previous own actually installed two ground straps to the firewall). I guess I need to do the C101 delete.

I went with lube locker gaskets too. Whoever changed the rear oil last time really believed more RTV is better, but it wasn't too difficult to remove. The old oil was dark but not thick. I had been worried they'd been allowed to leak out and run low, but both diff covers indicated they were still full to the plugs. I got the Valvoline synthetic at a decent price, the squeeze packs took delicate handling but got the job done. I found docs online saying the Dana 44 wanted like, 30+ ft lbs on the cover bolts, but I went with 25. Lowered that to 20 on the fronts. Probably overkill, I looked the cover bolt torque up in a service manual after I was done and I think the service manual said 14. Oh well, they don't leak. What's weirder is that my service docs said the 44 would take over 2 quarts of oil, but it started flowing out of the plug at a bit under 2. Same in the front (Dana 30), took a bit less than the rear, still under 2 quarts. Maybe I missed draining some, but both were flowing out of the plugs when I put it back in, so off we go. I was most curious about what look like scratch marks on the rear... carrier(?), er, that cage thing that rotates with the big gear and has the little gears inside it. It didn't look like there was anything for this to scrape against. I jacked up both rear wheels so I could spin them (LSD), and I did hear a sort of grinding sound as this thing rotated, but I don't think it was actually coming from inside the diff. I dunno, it's never made funny noises from the rear axle, and it drives normally so I guess these are just there from the factory or something.

Nope, I had the wheels off. I was putting the drum off and on while working the adjuster wheel. But I did notice you have to put the drum fully onto the studs when feeling out the shoes, same as if the wheel was bolted on. If I have to adjust with the wheels on I'm definitely getting one of those curved tools, I "practiced" going through the slot with a flathead screwdriver while the wheel was off and it was hard to get in the adjust notches. I would adjust it out until I had some resistance to turning, then I think I was backing off 10 clicks. The adjusters do turn easy. I did put a little copper anti-seize on the threads, but they still turned easily, I didn't want to impede the auto-adjust. I'm not sure I had them close enough to the correct setting though for them to actuate though.

I checked, they're 235 75R15, about 28 inches in diameter. Bigger than stock but not that much bigger. Doesn't sound like tire weight is an issue. Yep. I clicked the adjuster out until I could just slightly wiggle the new drums around on the shoes. It sounds like they're barely dragging if you put the drum on and turn the wheel, but I don't know exactly what proper drag sounds like. The pedal doesn't get stiff as you go further into it, which makes me think I've still got a bubble somewhere. But the fronts and rears are on separate lines now, I would think if one line was air free then that line would cause the pedal to get stiff, but I could be wrong about that. Is there a temperature I should see after a bit of hard braking? I could shoot the IR thermometer at the drums and rotors and see if they're getting merely warm or good and hot.

What I've seen indicates a faulty CPS is more apt to lead to hard crank, stalling and low power, and NOT idle issues. Is there a way to test the CPS? I haven't seen anything that talks about it. Most people seem to arrive at CPS diagnosis by way of elimination. I tested my TPS and it shows steadily increasing voltage over the whole throttle range, no gaps or drops in voltage. That's why I'm a little suspicious of the IAC. I did have the IAC off and spritzed some fuel cleaner in it, and a bit of black gunk came out, it might have been working poorly. The idle seems better but is still not the best. It doesn't surge through the 500-700-500 cycle as strongly as it used to, but does seem to idle more on the lower RPM side.

I gave that a shot this past Sunday. Went down to some abandoned farm roads and got it going a pretty good clip backwards then slammed on the brakes good and hard. I will say it brakes a little better now, but I still can't get anywhere close to locking anything up. I've wondered if the larger wheels and tires it came with might be adding enough weight to work against the brakes, but I doubt it. I'm overlooking something. The drums are new, so there's no wear-in. So when putting them on I could slip the drums over the shoes and wiggle them side to side to see exactly how much play I had, and it was very little. I also got out the calipers and checked the diameter across the shoes, it was well under 1/16th of an inch within the drums. I did clean the drums really well before I put them on. The parking brake still goes down almost as far as before the brake job, which does make me doubt my adjustment. I was thinking of getting one of those tools that measures inside the drums then shows you the same width to compare to the shoes. But the fronts never come close to locking either, which makes me wonder if it's a pressure thing. I adjusted the booster rod to touch the cylinder, or at least that's what my measurements were telling me.

For the record I pulled the throttle body, removed the IAC and TPS and cleaned up the body really well. It wasn't horrible but was due for a cleaning. I hit the connectors with electronics cleaner, re-assembled, adjusted and tested the TPS which showed to be okay (it could still be the engine side connection like cruiser said though). Anyway, it started and ran as normally as it ever has after that. We even had a nice little drive down to Rainbow Valley. Of course I left it running for this shot, set the brake and hopped out just long enough for a photo. No surprises thank you. I still feel like it's going to runaway idle again at some point though until whatever's causing it is explicitly addressed. Is there a good source for sensors, or the IAC? For a CPS I'd go with Mopar, but of course they're not what they used to be (nothing is).