Eagle

Because someday, somewhere, some Comanche owner is going to need them. Some of us are into MJs to see how badly we can mangle them. Other of us (cough, cough) are into restoring and preserving them.

AMC used the T-4/T-5 and the AX-4/AX-5 interchangably in the first couple of years of production. The specs call for the AX-4/AX-5, but when they ran low on trannies they pulled T-4s or T-5s from other production lines and used them in the XJ (and '86 MJ, rarely). They will interchange. But ... those trannies were used only with the '84 thru '86 2.8L V6. If the tranny you found is behind a 4.0L in-line 6, then (a) it won't fit your 2.5L (directly); and (B) it's not a T-4/T-5 or an AX-4/AX-5. Those trannies were not used behind the I6.

Do you know what engine and transmission were in the truck? It seems unlikely that it would have been a 3.55. That ratio was used only behind early 4-cylinder 4-speeds. It's more likely to be a 3.73 or a 4.10. (I think).

I'm having a hard time visualizing just where it snapped. Was the shock double-nutted? Was it only the threaded portion that snapped off? It looks like you also lost a portion of the actual solid post that the bushing rides on. It also appears that the remaining post is NOT long enough to fully support a bushing if you were to just clean up and square off the end, and weld a threaded stud onto it. Whatever you do, PLEASE don't carve up your old spring plate/shock mount. By pure coincidence (have I mentioned previously that I don't believe in coincidence?), I happen to have an old bag of Monroe supplemental hardware that consists of a complete replacement stud assembly. I will gladly send it to you in exchange for your promise to retain the old lower mounts in stock form, just in case some other MJer needs one in the future. The Monroe stud has an oversized head, that could be ground flat and welded to your frame, or there may be a better way to use it but it's about 12 degrees at the moment and I am not about to go crawl under mine to figure out what that better way might be. I don't have a scanner but if you have access to a fax, I can fax the diagram off the package and sent it to you. You can use that to determine if this thingie might be what you need. Lemme know by PM.

The u-joint is the same, but the pinion snout on the 8.25 is about 5/8" longer than the D35 so you may have to shorten your driveshaft.

The ZJ front axle will bolt into your MJ but, as noted, it's a low pinion. That wouldn't matter at stock height, but it magnifies u-joint angularity issues if you lift. BUT ... it will be a non-disconnect axle, and it should have the larger 297 u-joints on the shafts. And you should be able to grab the front driveshaft as a spare. The brakes will be the crappy Chrysler composite rotors that warp if you look at them cross-eyed, so probably the best deal might be just grabbing the axle shafts, and then you could convert your MJ to the larger u-joints and a one-piece shaft w/o disconnect. Do NOT use the ZJ hubs on your MJ -- the knuckles are different, and the hubs do not interchange. A V8 ZJ probably has the aluminum case D44, which isn't really a D44. If there was ever an axle that's WORSE than the D35 ... that's it. It might serve as a donor o=for a rear disc brake conversion on your existing axle, but don't bother putting the ZJ axle into the MJ. The transfer case will be a 23-spline, so it won't mate to your '88 transmission. Also, the early ZJs used a transfer case that didn't lock the driveshafts in the 4-Hi mode. I don't know what year they stopped doing that. If you are even considering adapting that t-case to work in your MJ, be sure to verify which t-case it is, because it may not be worth the effort. Rims will definitely swap right onto the MJ. The steering box is the same, so you could grab that as a spare. And the front coils on a V8 ZJ should be essentially like Up Country coils in an XJ/MJ ... about a 1" lift over stock. That's about it.

My '88 MJ apparently had factory foglights. The switch is on the dashboard. It had no lights when I bought it and I haven't traced the wiring, but there is a relay on the driver's side radiator side brace that doesn't exist on my '88 XJ, so I believe that's where the foglight relay should be.

CO is carbon monoxide. That's not unburned fuel. Hydrocarbons is unburned fuel.

I got dibs on the MJ from "Monster's Ball," but only if I get Halle Berry with it.

If you replace the catalytic converter, you should also replace the O2 sensor, because if the O2 sensor is bad, the amount of unburned stuff going down the pipe will burn out the new cat ASAP. Personally, I would replace the O2 sensor first, and then do the cat if it still fails. If you're fairly certain you need a cat, do the O2 sensor at the same time.

Yeah, Pete, but you are quoting from a write-up about replacing an AX-5 with an AX-15. That means mating the AX-15 to an engine (and crankshaft) that Jeep never mated it to. This thread is about replacing a BA 10/5 with an AX-15. Both of those were 4.0L transmissions, so it's reasonable to think that Jeep has pilot bearings for them to work with the 4.0L engine.

I ran my MJ with 31x10.50s on stock 7" rims for several years and I didn't notice any odd or accelerated tire wear.

Why would you need a pilot bearing from another Jeep? The XJ and MJ were offered with both the BA 10/5 and the AX-15 ... just buy the correct bearing for the tranny and install it.

NOx is usually a product of high combustion temperatures, which can be brought on by a lean-burn condition. What I did NOT see on your list of things replaced is the oxygen sensor. The O2 sensor is a scheduled maintenance item that should be replaced every 80,000 miles. (I use 75,000 as the interval because the multiples are easier to keep track of mentally.) The two most common cause of emissions failure for the 4.0L engine are the O2 sensor, followed by the catalytic converter. [EDIT]Oops ... mis-read your post. So you're okay on NOx but bad on CO. I still wonder when you last replaced the O2 sensor.

The 1984 - 1986 Jeep 2.8L V6 IS a GM 2.8L engine. Any transmission you can find bolted up to a GM 2.8L (or rear-wheel drive 3.1L or 3.4L) engine will bolt up to your Jeep 2.5L engine. The 2.5L was engineered to share the same bell housing-to-block bolt pattern as the GM 2.8L. The only question is whether or not your transfer case will mate up to the transmission.

Are you swapping to the new style dashboard? If not, you don't want a '97-'01 interior harness, you want a '91-'95 harness. But the gauge polarity was reversed in the 1991 model year, so you'll have to replace the instrument cluster, and the '91 and newer use an electronic speedo (although I suppose you could probably fit your mechanical speedo into the newer cluster, but I haven't tried that to verify it).

I am well aware that the US military uses synthetics in all vehicles. I am also aware that the US military isn't running a whole lot of XJs and MJs with the AW4 transmission, and any they have either came from the factory with synthetic or were converted upon delivery. You are free to do as you wish, Sir, but the kind of people on NAXJA who have encountered this problem are not the typical "drive it 'til it drops" kind of owner who would ignore normal maintenance. As I wrote, enough people have noted that converting the AW4 to synthetic kills the transmission that I am not willing to risk it. These people, generally, made the attempt because they had not encountered this problem with other automatic transmissions. They did encounter it with the AW4. Take it for what it's worth.

I wouldn't box the rockers for a daily driver. You can buy replacement rocker panels from most of the aftermarket body parts companies for not a lot of money, and they fit pretty well. Dunno if they still have them, but a few years ago I got a set from JC Whitney.

What vehicle did you get the booster out of, and how much custom fitting did you have to do to make it work?

They'll fit with no lift, if you're on stock Jeep rims. However, with OR without the lift, at full steering lock (when you turn the wheel all the way left or right) they are going to rub on the lower control arms. This condition is not helped by a lift.

Most of the 2.8L automatics came with 3.73 gearing, and that's actually an excellent ratio for a 4.0L automatic. Especially if you run tires slightly larger than stock, like maybe 235/75-15s or 30x9.50-15s. Just swap in the speedo gear from your old transfer case and you should be all set (but check the shaft length on the two speedo gears, they may not be the same).

Yes, I know. It won't. They are TOTALLY different. Right down the the polarity of the gauges being reversed.

I strongly advise you NOT to use synthetic in the transmission. Why? Not from my own experience, because I'm a 5-speed kind of guy. But I've been a member of NAXJA since it was founded, and ALL reports from the NAXJA tech forums are that synthetic tranny juice is death to the AW4 transmission. Nobody knows exactly why, there are several theories, but my view is ... why argue against the collective wisdom of several thousand serious owners? Enough people have reported problems that I do not wish to tempt fate. I run my wife's XJ on Castrol full syhthetic in the engine, but the AW4 (which is due for a change) gets conventional.

Oops. Yeah, the pan full of metal chips would definitely be "a clue." Bummer.

185,000 kilometers? That's only about 111,000 miles. My '88 XJ Pioneer (with the original Peugeot transmission) is currently at 266,000 and change ... MILES. The Peugeot tranny gets a bad rap. There's nothing wrong with it if you don't mistreat it, or think it's a drag race vehicle and insist on making every shift a power shift. $200? Canadian? That's not a bargain, it's a steal. Don't let it get away.