Eagle

No you didn't. The '98 Grand Cherokee didn't have the AW4. The Chrysler 42RE replaced the AW4 midyear in the 1993 production run.

He's trying to do a complete engine balance. That's only for "real" race cars that are going to be run hard and long at sustained high RPM (like 7500 RPM and higher). That level of balancing is completely unnecessary for a street vehicle.

If a synchronizer slipped out of engagement, you'll effectively be in neutral and you won't be sending any power to the wheels. It's usually the second gear synchro that buys the farm -- I've never heard of fifth gear or the fifth gear synchro failing, but there's a first time for everything. Possibly just the shifter out of alignment?

It has been posted here before. Long or short wheelbase?

Yes, the clutch release bearing is also called the throwout bearing. Replacing it does require dropping the transmission, but it does not require disassembling the transmission. It's in the bellhousing. But the clutch release bearing wouldn't make noise only in fifth gear. (Unless that's the only gear you can hear it in.)

Are you sure the noise is in the tranny and not the clutch release bearing?

The XJ seats that cause the problems with height are the ones from the late 80s models that had the "rocking chair" seat cusion adjustment as well as the standard recliner in the seat back. The rocking chair mechanism adds a layer of hardware that in the XJ required a lower seat pedestal to compensate. There is no lower pedestal for the MJ. Find XJ buckets that don't have the rocking chair feature and you should be okay.

The heater core in my '88 Cherokee popped about four or five years ago. If yours is the original, it's on borrowed time. Much better to start new since you'll be in there anyway. Ditto for the evaporator.

The only part of a clutch assembly that makes any contact with the transmission is the splined center hub on the disk. The pressure plate, which is the part that you bolt to the flywheel, obviously has to match the flywheel.

I've always used black Permatex (not RTV) for installing freeze plugs. Never had one pop out. FWIW, the factory pressure cap is 13 psi.

The front axle is the same for an XJ and an MJ. No issue there (other than recreating the original mounts!) The XJ rear is a spring-over-axle. The MJ is a spring-under axle, and the spacing between the spring perches is slightly different from the XJ to the MJ. It just means welding on a pair of new spring perches, or carefully cutting the old ones off and relocating them.

Not to beat a dead horse, the symptoms you describe are the classic symptoms of out-of-balance tires.

Have the tires balanced again. The symptoms you describe are classic for out-of-balance tires.

If you still have the height-sensing valve and the line feeding it, there's a special procedure to ensure that line also gets bled. It's been posted here several times. Try a search -- or maybe someone has it bookmarked.

Does this guy know the difference between a counter-weighted flywheel and a neutrally balanced flywheel? I have alo never heard of anyone trying to balance the flywheel with the crank when doing this swap. IMHO it's not necessary and it's an invitation to screw something up. Tell him to balance the flywheel. What will cause those vibrations he's talking about would be using the counter-weighted 2.8L flywheel on the 3.4L crank. I've been through that many years ago, in a different vehicle with a different engine combination. Some previous owner tossed in a junkyard engine of a different displacement than the original, but he used the original flywheel -- which was (like the 2.8L) counterweighted. The junkyard engine needed a neutral-balanced flywheel. Once I got the thing running it had a nasty vibration. Took a bit of detective work to figure out what had happened. Bought a used flywheel that was correct for the engine, bolted it in, and it ran as smooth as silk. Leave the crankshaft alone.

The flywheel and torque converter don't affect 2WD or 4WD. You need a transmission from a 4WD so the output shaft and housing can mate up the the 4WD transfer case.

Many of us run 235s, but the factory sizes were 195/75, 205/75, 215/75 and 225/75.

Luk is (was) the OEM supplier.

8" is too wide for stock size tires. The factory rims were all 6" or 7". And with only 4" of backspacing I would expect some interference when turning. For example, the specs for a Goodyear Wrangler SR-A in 225/75-15 call for an approved rim width of 6.0 to 7.5 inches. If I look at tires in the 205/75-15 size, the approved rim width is 5.0 to 7.0.

The seats and mounts are different. You might be able to adapt the Cherokee seats to the MJ pedestals, but it won't be a drop-in swap. The console will require modifications. I don't think the late model window motors will work in the early doors, but I'm not certain. Your MJ has a mechanical speedometer. The '97 Cherokee has an electronic speedo. Beyond that, the '97 cluster won't fit your '88 dashboard, so you would be looking at a total dashboard swap.

Of course the speedo gear won't affect the tachometer. But the tachometer only tells you the engine speed, not the road speed. Unless the speedometer reads correctly, you can't know how many RPMs the engine is turning at _X_ MPH. Any time you change tire size or gear ratio without changing the speedometer gear, you make the speedometer inaccurate.

Factory? The Custom 4x4 tow hook kit has brackets that are pretty near clones of the factory brackets --- with one exception. If you look at the ones in Jim's opening photo, there are two sets of holes. The brackets are mounted using the forward set of holes if you just want tow hooks. If you use the rear set of mounting holes, it moves the bumber out by six or eight inches to provide space for the Hidden Winch option.

There are some parts missing. From the factory parts manual:

Chrome plated -- they'll turn to rust in a year. Do they take a 3/4" socket, or do they need a 13/16" socket?

If it had tow hooks from the factory, it also had skid plates: front, transfer case, and gas tank. Not too long ago I think someone (might even have been me) post an exploded view of the front skid installation. The other two are fairly easy to figure out. This may help: http://www.olypen.com/craigh/skid.htm There is no source for factory skids -- they don't exist. If you want the factory types, you need a junkyard.