AZJeff

I have owned Several XJ’s and an MJ with the 4.0, and all of them need hellishly high belt tension to avoid squealing. My approach is to Tighten the belt “very tight” based on previous experience, and then drive the vehicle from a cold start using the A/C to put the max load on the belt. Invariably, my tension is inadequate, and the belt squeals. So, I tighten it a bit more and try again. Sometimes I have to do this 2 or 3 times before I get the tension high enough. The point of all this is that even with a tension gauge, it’s best to do an “approach to zero squeal” to get optimum belt tension.

Good to know, thanks.

Agreed. The ball joint type upper end of the XJ/MJ track bar is one of the less-than-stellar parts of the vehicles design. Swapping it out to another approach is an improvement.

I would contact Rock Auto about any warranty it might have. If it hasn’t been submerged, two months is a pretty short life expectancy for a bearing, even if overloaded due to excessive belt tension

I am well versed on booster function tests, and I am certain my booster was functioning as intended. I remain convinced my old 1992 XJ brakes were marginal at best, and that the later booster is a significant upgrade. Caveat—I have never driven an MJ with stock brakes, but I cannot think they would be massively different than an XJ of the same era.

Rear discs never appeared on the MJ nor the XJ during it's production runs. Rear discs first showed up on the ZJ, and were back compatible to the MJ/XJ chassis due to extreme similarity.

I dunno. My first XJ sat on stock wheels and about the biggest tire I could fit without a lift, but I don't remember the exact size. That beast could NOT lock up it's brakes until I did the booster upgrade. I know your experience on the XJ/MJ chassis exceeds mine from the days when I lurked on XJ forums. None the less, there must have been a good reason Chrysler upgraded the booster design, and that is why I did it to my MJ when I got it.

Its interesting you say that, because my 1992XJ had HORRIBLE brakes, even after I rebuilt the drums in the back and replaced the calipers up front back when it was about 10 years old. I literally could stand on the pedal and not lock them up. I was new to the XJ/MJ chassis at the time, and read up on how Jeep had created the improved dual diaphram power booster and MC. I decided to put that in my XJ, and the improvement was quite noticeable. It's possible I had a bad booster before, but it didn't show any symptoms when I did the classic booster function test.

I will also add that early XJ’s (and their MJ cousin) don’t exactly have the best boost levels for their power brakes. The later XJ’s addressed this with a dual-diaphragm power booster, and I would consider this an almost mandatory upgrade when doing a brake system overhaul on these vehicles.

The cooling system on the XJ and MJ vehicles are, under the best of conditions, just barely able to handle the “worst case” heat load from the engine. It’s the Achilles Heel of the beast. Deterioration of system parts often pushes the system into the overheating mode. The older ones with “Closed” cooling system are even MORE sensitive to the deterioration issues. If you blew one hose, it’s a good bet they are ALL in bad shape. also, the pressure tank and it’s cap on the closed systems is prone to leaking and/or bursting with old age. Finally, you say you removed the t’stat. Was that in hopes of lowering cooling system pressures? If so, that is NOT going to fix the issue, as the t’stat controls the MINIMUM operating temperature once warmed up, NOT the maximum temperature. Stick a good 195* thermostat back in the system when you replace all the hoses. Lastly, what temperatures is your engine actually seeing when warmed up running at say, 30mph?

If you can’t get your impact in there, you can jam a short stout screwdriver though one of the spokes on the HB, and wedge it under the shelf of the engine block where the oil pan attaches. That will hold the HB while you use a breaker bar to free the bolt.

Mine is located there because I have a driveline from a 2001XJ, but moving it frees up space in the engine bay, and doesn’t cause any issues for the undercarriage if done well.

I am two for two using CSF. Neither had the issues reported by the OP. if I was the OP, I would return thatrad. and insist on a different one from Rock Auto.

CSF rads use a regular cap. I personally would not use a junk yard cap, given that an appropriate 16lb cap is so inexpensive at all the big box auto parts stores.

I agree with Eagle. I am betting other parts are FAR more likely to be the cause of your issue before control arms and their bushings.

That might work in NC. Here in AZ, dry rot on a 20+ year old hose is almost certain.

I wouldn't put a junkyard hose on an AC system except under duress. The combination of possible contamination, along with dry rot, make it a poor choice.

The most commonly recommended course of action here for ANY reports of wandering is to do a thorough examination from underneath the vehicle. This requires a helper to do it well, and here is the method: Have the helper sit in the vehicle, with the steering column unlocked. His/her job is to turn the steering wheel back and forth JUST ENOUGH to load all the steering linkage to the point where the wheels are starting to move off of center. While they are doing that, you are lying under the vehicle and doing a visual examination of every joint or fitting in the entire suspension. A flashlight helps to see motion between the two parts of the joint. Also, any rubber joints that look dried out/cracked and distorted are targets for replacement, regardless of relative motion. I also like placing my hand around the steering linkage joints. Don't use a death grip around the two parts, but be firm enough that you can feel relative motion between the two parts of the joint.

What did they use for the OEM carb. back then? Just curious.

Another one more knowledgeable than I when it comes to very early Comanche's and Cherokee's.

One more knowledgeable than I has spoken. Good post.

The AW-4 neutral switch is attached to the gear select shaft, not like what is shown in the above photo. Of course, the AW-4 was used with the 4.0L straight six. I don't know which auto trans was used on the V-6 equipped MJ/XJ vehicles, and don't have a shop manual that goes that far back. Sorry...

I can appreciate doing that job under less-than-ideal conditions. It's a HUGE PITA.

This activity is where an air hammer with a slitting type chisel tip works WONDERS at getting those bushings out.

Original sub-model is unknown to me. It's a SWB. Now equipped with 4.0L/AW-4/NP231 from a 2001 XJ. Front axle is low pinion D30. Rear axle is D44. Front sheet metal and doors are from 2000 XJ, as is dashboard/console. Vehicle is painted in color found on 2011 JK called "Mango Tango Metallic" Now sports 3.5 inch lift, ZJ rear disk brakes, and 17" "Moab" wheels from Jeep Wrangler. I use it as a semi-daily driver, with my 2014 JK as a backup.