Eagle

Agreed. Also not worth $64.90, or even $6.49

Most (but not all) 4-cylinder XJs and MJs (especially those with 5-speeds) came with 4.10 gears. [4-cylinders with 4-speeds generally had 3.54 gears, and some early 4-cylinder automatics had 4.56 gearing.] The front axles usually have a tag on the outside showing the gear ratio.

The solution is probably to rip out that entire rat's nest of wiring and start over from a clean slate. The Mopar Performance Catalog used to sell a complete fuel injection conversion for the carbureted YJs. It was basically the engine harness, fuel injection, and ECU from a 95 Wrangler, packaged as a stand-alone system. Something like that is what your friend needs. He already has the manifolds, the injection, and the throttle body. He needs the harness and the computer. (And maybe the fuel pump.) Time to hit the junkyards. http://www.fourwheeler.com/how-to/129-0309-efi-fuel-injection-258ci-jeep/

Ugly.

Only once? I should be buying those resistor packs by the case. And, yes -- when the little rascals build their nest in there, it does create smoke and a burning smell. For awhile -- then the thermal fuse pops, and you have a single-speed fan -- it's either off, or high speed, nothing in between.

The 8.8 also requires an adapter for the rear u-joint on the drive shaft. The KJ axle is a much easier, more straightforward swap.

You could install a Comanche Dana 35, but you would have to relocate the spring perches. Or you could install a Cherokee Dana 35 -- and you would still have to relocate the spring perches. But a Dana 35 is not a good axle. The only reason for using one would be if it's for an MJ, you want to revert to the original SUA setup ... and someone gives you the axle. Bottom line: if you want to stay with spring-over-axle, there is no axle you can use that won't require welding spring perches in the correct location. For the $100 that D35 would cost you, you could probably find an un-welded 8.25 differential and just install that in the axle you have. Just be sure to measure the diameter of your axle shafts, to see if you have an early or late 8.25.

How do you install either a KJ axle or an 8.8 axle in an MJ without welding?

He wouldn't need the computer to adjust for spark. The distributor does it. What was arguably the first automobile dates all the way to 1808. The first vehicles that were more or less practical came along in 1870. That means we managed to have internal combustion engines driving cars for more than 100 years before some genius decided it was a good idea to use computers to control them. We have a member here who is running his MJ with a distributor from a Jeep 4.2L engine. It can be done. The question is whether the computer will handle the injectors without a signal from the immobilizer circuit.

Your opening post said it doesn't crank. Turning over is cranking. So apparently your problem is that is DOES crank, but it doesn't fire. If the problem is the security system, I don't think the new ECM will solve the problem, since the problem originates in the BCM, but please keep us posted with results. If it were mine, I'd go back to the CJ electronic ignition and start driving.

So you're saying the starter doesn't have power? Or the starter has power but doesn't turn the engine? What's the problem you're trying to solve?

No, I don't think so. The XJ studs are still on the axle, but MJ rear shocks mount to studs on the spring plates, and there are corresponding mounting studs on the inside of the frame rails. I don't see those in your photos -- I think they've been cut off. Here's a photo from another thread that shows the lower mounts pretty well. The uppers are hard to see. Does anyone have a photo of the stock shock mounts they can post? (Preferably for a longbed.)

I just noticed that there don't appear to be any shocks in the rear, and it looks like both the upper and lower shock mount studs were cut off.

I don't have much to add, except that the reason your rear brakes don't work is that the lever arm for the height-sensing valve (as has already been mentioned) is hanging down instead of horizontal or slightly above horizontal, where it should be. As for the rear axle, if you can find new guts for for the diff you can just replace the differential, but given that the perches are in the wrong locations it might make more sense to just buy a complete rear axle out of a 4.0L XJ automatic, relocate the perches to where they should be, and then install the whole thing. While you're in the differential you could also install a lunchbox locker or a limited slip. If you can live with a limited slip, then you could just buy it and install it in the axle you have. But the spring perches still need to be cut off and relocated. The comment about the missing front sway bar links is VERY important. It is NOT safe to drive any Jeep on the street without the sway bar being connected and functioning. The front track bar is Rusty's. It's a piece of crap. I had one and the tie rod end on the frame end lasted less than a year. A friend in NAXJA-NAC had one that failed catastrophically on a trail -- the threaded bung on the frame end pulled right out of the tube, leaving him with no track bar -- which means no steering.

Check the VIN

I agree with Don. Don't try to create work-arounds -- that's what generates all the "I have no idea what the previous owner of my Jeep did" posts regarding wiring. Get a copy of the factory wiring diagrams, and fix it so it works the way it was designed. That way, you can always come back and fix it again if something breaks, and you don't have to try and remember what you did.

"Renix" is a contraction. The system was a joint venture between Renault (which owned Jeep at the time) and Bendix, so the names were combined into RenaultBendix ==> Renix.

Sorry, but you're wrong. From page 8 of the 1994 Jeep FSM for Cherokee and Wrangler: I'm pretty certain you'll find basically the same statement in all the factory service manuals.

Basically anything other than "clean, dry" threads requires a reduction. For things that may loosen from vibration, I often used thread locker (a.k.a. Loctite). That also requires a reduction in torque, although some sources suggest not reducing by 20% to 25% with thread locker. The deal is that bolts hold thing together by stretching slightly, but within the "elastic limit" of the steel. Just like the tension when you stretch a rubber band, the tension created when you stretch a bolt generates the clamping force that holds the parts together. Engineers decide how much clamping force they need, and specify the torque needed to generate that much force. Turning a threaded bolt is like pushing a weight up an inclined ramp. Put some oil or grease on the bottom of the weight, and it slides up easier so you need less force to push the same weight. That's torque -- with lubricated threads, you need less applied torque to generate the same stretch in the bolt. And, as gogmorgo mentioned -- especially with small bolts, if you exceed the elastic limit of the bolt -- it necks down (stretches beyond the elastic limit) and breaks. For what it's worth, by the way, before posting my advisory above I did a Google search to try to find authoritative sources to steer you guys to. What I found was mostly discussion forums, and a lot of self-proclaimed "experts" who pooh-poohed the notion of reducing torque when using anti-seize. (I also found some who pooh-poohed the notion of using anti-seize at all -- are you kidding me?) Just remember -- unless otherwise stipulated, published torque values are for "clean, dry" threads.

Probably doesn't apply to the plastic valve cover but, since we're talking about torque values -- remember that most torque specs are based on "clean, dry" threads. If you use anti-seize (as I do on everything), the torque has to be reduced. The percentage of reduction depends on the diameter and thread pitch -- a general rule-of-thumb I have always followed is 20 percent, but I just found a source that says 25 percent: http://www.antiseize.com/PDFs/torque_specifications.pdf

What automatic serpentine belt tensioner? I have two 2000 Cherokee 4.0Ls. They don't have an automatic tensioner, I have to do it manually.

It could be the slave cylinder, it could be the master cylinder, or it could be the line connecting the two.

Comanches are hybrids -- the cab is unibody, exactly like the Cherokee. The back has a somewhat conventional frame and the bad can be removed, but with the front being unibody that doesn't help any with respect to a lift. Cherokee lift kits work for the front, but not for the rear.

Agreed. The ventilator fan runs in bronze bushings, not roller bearings. If your's isn't too far gone, you can drible a couple of drops of oil into it. On the end with the squirrel cage, ideally remove the impeller and drop the oil on the shaft (not too much), then replace the impeller. On the other end, drill a small home in the center of the bump where the end of the shaft is, drop in a bit of oil, then put a piece of tape over the hole.

Measuring from the axle centerline to the flare (body) doesn't eliminate half the tire and wheel diameter, it eliminates all of it. Doing the measurement from the axle to the body means the axle can be sitting on jackstands, with no tires or wheels on the vehicle, and you're measuring where the springs carry the body relative to the axle. Yes, assuming the tires and wheels haven't changed measuring from the ground does provide a before and after differential -- but it doesn't provide any baseline for establishing whether or not the before measurement indicates sagged springs, or (if so) how much. All you know is that you changed the ride height by 'X' inches. Example -- a number of years ago I fixed up an '88 XJ for a former girlfriend. The rear was sagging, so I did a home-brew AAL by adding a second XJ main leaf with the eyes cut off on each side. The gross change was 1-1/4" of lift. But, when the dimension from the axle to the flare was measured after the "lift," it measured 17-1/2 inches. Stock for an XJ in the rear was 17 inches, so I had taken out 3/4 of an inch of sag, and actually lifted the rear only a half inch.