Eagle

Take a look down the bore with the engine off. The throttle plate should be closed. Idle air should be delivered through a by-pass port that's only there for idle. If there's a gap between the throttle plate and the bore, the idle speed screw isn't allowing the throttle plate to close completely. Or it might be held open by the choke. Does it idle too fast when fully up to temperature, or only when first started cold?

IIRC, the MJ center bolts are larger than XJ center bolts. I want to say they're 5/16" but I'm not certain of that. Pro tip -- do NOT try to use the bolt and nut to pull the leaves together. Use a heavy duty C-clamp (or two) to clamp the leaves, tighten the nuts on the through bolts, and then release the C-clamps. If you buy socket-head cap screws at Lowe's or Home Depot (or probably anywhere), the head diameter may be sightly too large to fit the hole in the u-bolt plate. Be sure to check that first, and grind them down to fit if necessary.

You should be able to get a replacement cord (universal) from Lowe's or Home Despot. With a plastic body, I would not be surprised if that saw uses sintered bronze bushings rather than bearings. (Like the XJ/MJ fan motors.) Try oiling the bushings or bearings and see if it helps. Ultimately, you may have to replace.

Auto theft goes high tech -- thanks, Apple. https://www.fox4news.com/news/man-finds-apple-air-tag-tracker-on-his-dodge-charger

Another

What do you mean by "I replaced all the ignition"? And how long does it take to start? Have you driven THIS vehicle through other winters? If so, is it significantly worse than it was last year or the year before? Gasoline is less volatile when it's cold, so it's normal for starting to take a bit more effort when it gets down toward (or below) freezing.

The good freeware programs are all updated regularly. I use several of them.

I'm looking for some feedback on a potential book concept. I'm not a master of science fiction, or any fiction genre. I enjoy writing, but I seem to be more of an explainer than a creator. Having lived on a rather limited (and limiting) budget for a number of years, I have become a huge fan of freeware software. Although some freeware is complete dreck, some of it is really excellent. I don't know how many people are even aware of freeware, or just how prolific the freeware community is. Since I use several freeware programs in my home office (and could use more if I shed a few commercial programs that I still use), I have what may be a better appreciation than most for what's out there. The thought occurred to me that there might be a potential market for a book informing people who might be looking to set up a home office or small business on a tight budget of what programs are out there that can be used to equip a home office -- for free or nearly free. The intended target audience would probably be older folks (like me), who are maybe retired or soon-to-be retired, who have used Microsoft Office at work and who don't want to shell out big bucks to buy MS Office for home, and don't want to get sucked into a subscription for Office 365. So I would be discussing office suites, and then also get into graphics programs, CADD programs, possibly video editing programs, and accounting. Does anyone think there would be a market for such a book?

Whether you keep it or sell it, it's definitely not worth paying a shop to make the swap. IMHO it's definitely worthwhile if you do the work. There's nothing complicated about it -- it's all bolt-in parts except for having the rear driveshaft modified. Find a Cherokee donor vehicle and just move the parts over. Just be certain that the donor vehicle has the same gear ratio as your 2WD rear axle.

The first option above - just eliminating the rear height sensing valve - will leave you with 100% full braking power to the rear wheels at all times. Since normally about 60% of the weight is on the front wheels, and that increases when you brake, having full power to the rear brakes at all times often results in premature lockup even with the factory drum brakes. With rear disk brakes I would expect it to be worse. The problem with premature rear lockup is that it usually causes a spin-out. The WJ proportioning valve is a proportioning valve, designed and intended to reduce premature rear wheel lockup. If you are going to rear disks, IMHO you definitely need some kind of proportioning valve. Whether the WJ unit is the best choice, I don't know.

Try to salvage anything that's unique to the MJ, such as the parking brake pedal assembly, the seat brackets (even if the seats themselves are toast), the rear proportioning valve, spare tire winch (if it works) -- things like that.

I agree. I don't care if they know your mother. If that's the kind of work they do for friends, just think what they do to customers who aren't friends. Either find a decent shop, or figure it out for yourself. I wouldn't allow that shop to touch my truck, ever again.

You have a vacuum leak somewhere. There's a rat's nest of small vacuum tubes under the dashboard -- I think you're going to have to go hunting until you find the one that's causing the problem.

Auburn offers three different types of replacement differential. The one we used to see when I was active in NAXJA-NAC was the "Grip-N-Loc," which is a standard, clutch type limited slip that uses a cone-shaped clutch pack. Then there are two flavors of "Select-A-Loc." One runs normally as a clutch-type limited slip, and has an electrically-activated locker function for more positive locking. The other is an electrically-activated locker that is an open differential, rather than a limited slip, when not locked by the electrically activated locker. The lockers in both Select-A-Loc units are mechanical, not clutch operated. For a D30 front axle, I would go with a Detroit True-Trac.

The Auburns are limited slips, and use clutches. The G80 is a locker. I don't think it uses clutches. https://www.topspeed.com/cars/car-news/deep-dive-general-motors-g80-locking-rear-differential-ar169064.html

It hasn't happened to me, but there have been reports of the frame cracking at the steering box in both MJs and XJs. There are aftermarket parts to brace the steering box, and kits to plate the frame in that area for extra strength. What size tires do you run, how much rock crawling do you do, and how often do you turn the steering wheel when the vehicle isn't rolling?

I'm not sure why what I wrote cancels out the aftermarket adjustable proportioning valve but, if that's a deal-breaker for you, so be it. I don't think you can buy a new distribution block for the MJ, and it's unique -- totally unlike the XJ/ZJ/TJ proportioning valve. If you are going to open it up and clean it out, consider opening up the ID on the ports. Cruiser has made some measurements, which should be posted around here somewhere, which showed that for some reason the orifices on the MJ distro block are smaller than on the XJ/ZJ proportioning valve. IMHO it can't hurt to open them up slightly to match the size of the orifices in the XJ/ZJ units.

Confirmed. For the Dana 30, the carriers used are divided into 3.54 and lower numerically, and 3.73 and higher numerically. This is usually referred to as the “carrier break.

That's a good choice, BUT ... pay attention to this from the instructions: By using this proportioning valve, you will lose the warning light that's intended to signal the loss of the front or rear brake circuit. Technically, I think that may be illegal -- but I think most of us know the difference between a firm pedal and the low pedal that results when you lose half your brakes, so I would be concerned about this only if you live in a place that requires annual safety inspections and the inspection verifies that the warning light is present and functional. And this unit is also a work-around if you've swapped in a different brake pedal setup from a different year, and the mechanical switch isn't getting the job done. This allows you to remove the mechanical switch in the pedal assembly and just extend the two wires through the firewall to the pressure switch on the proportioning valve. Also note that two of your hard lines use a 1/2-20 flare nut, and this unit uses all 3/8-16 flare nuts. So you will have to re-make or adapt two of your lines.

So you're looking for what is generally referred to as an "RV" cam rather than a "performance" cam.

Photo of the distribution block: The XJ/ZJ block is also a proportioning valve. The MJ is not. They look similar on the outside but the internals are different.

Rancho has a rear AAL kit that they advertise as 2-1/2 inches for the XJ and the MJ. Since the XJ is spring over and the MJ is spring under, it can't be the same for both vehicles. I called Rancho and talked to their engineers. It's actually 1-1/2 inches of lift in the MJ.

What kind of performance? Low end grunt power, or high RPM horsepower?

You don't have a proportioning valve -- you wrote that you deleted it. Sounds to me like a bad caliper.

The stock setup with auto (225/75-15 tires with 3.55 gears) turns 2100 RPM at 65 MPH in over drive. 31x10.50-15s with 3.73 gears turn 2085 RPM at 65 MPH. In other words, 31" tires with 3.73 gears are effectively exactly the same as a stock automatic. My rule of thumb is that 3.73 gears are about perfect for 30" tires, 4.10s are good for 31" tires, and for anything bigger than 31s you need at least 4.56 gears. If you run a Dana 30 front axle, last I knew the steepest gearing you could buy was 4.88, and those have such a small pinion that's it's rather weak setup. If you use one of the "Dana 44" front axles out of a TJ Rubicon, the bigger pumpkin will allow you to get into deeper gearing -- but it's a low pinion axle. 31x10.50-15s with 4.10 gearing turn 2292 (call it 2300) RPM at 65 MPH. That's not bad for highway work. My frame of reference, for those of you worrying about "burning up" the engine, is the AMC cars these engines were originally designed for. My family was an AMC family. We owned just about every early variation of the engine: 199 c.i.d, 232 c.i.d, and 258 c.i.d. They didn't have over drive in those days, and the models with standard transmission were geared to run 24 MPH per 1,000 RPM. That means 60 MPH was 2500 RPM, and 3000 RPM was a 72 MPH cruise. And the engines easily went well over 200,000 miles. Jeff, a bit more crunching shows me that in overdrive you are turning 1904 RPM at 65 MPH. That's actually below the torque peak for the engine, so it's not a surprise it won't pull long upgrades on the highway. When you lock it out of overdrive, in third gear you're turning 2539 RPM. 4.10 gears will get you to 2205 RPM, which kind of splits the difference. But the torque peak for the 2000 XJ engine is at 3,000 RPM, so you'd still be well below the torque peak. 4.56 gears would get you closer -- 2453 RPM. But that's very close to what you're turning when you just lock it in third gear, so I don't know if you want to live there all the time or not.