Eagle

No recent experience with Rusty's junk. "Once bitten, twice shy." My primary question is, how can you tell from looking at their kit (on their web site?) that they've tried to remedy "some" of the complaints. The complaints that I had and that everyone else I knew who tried Rusty's crap was that the quality wasn't there. At least one of the failures could have been fatal. I had one of his adjustable track bars on which the upper TRE wore out in a lot less than 10,000 miles. One of my friends in NAXJA/NAC didn't do quite that well -- on his, the threaded bung in the upper end broke the welds and pulled right out of the tube, leaving him with NO steering. It happened at low speed on a trail, so no injuries. What might have happened if it had decided to pull out on the highway at 65 MPH?

The wire in that photo does not look at all like a factory wire or a factory wire terminal.

The seat, that I agree with. The stock bench seat in my red '88 is badly bent/broken down on the outer edge. I think that's partially due to the 4" lift that was in the truck when I bought it. I'm 6'-1" and the lift put the seat at just the height that my entire weight had to slide over the extreme edge and outer front corner of the seat when entering or exiting the truck. Once I had removed the lift, my feet could reach the ground for a normal mount or dismount.

But it is NOT a characteristic of old Jeeps (or old vehicles of any description) unless most such vehicles exhibit the same behavior. I currently own an 87 MJ and two '88 MJs. Others that have passed through my hands include three 86s and an 89. My buddy down the road had an '87, another friend has an '89. A guy I work with has an '87. None of them exhibit sag to either side, and I can't recall ever seeing or hearing of one with significant sag to the driver's side. If it doesn't affect a significant majority of the vehicles, it isn't a "characteristic," no matter how badly one or two isolated vehicles might have failed.

Yes, and no. Or ... maybe. Yes, in that I can certainly read off the data, enter it on a spreadsheet, and chart it the same as the one I have already done. I guess I'll have to look up the formula for computing horsepower from torque, and see how that works out. Is this from yours, Don? What's the source of the stock readings? Ideally, I'm looking for factory numbers in order to compare different years on an even footing, but it would also be interesting to compare a real world example against the factory numbers to see how much the factory fudged the numbers. I'm having trouble reading it, though. Where is 1,000 RPM -- is it midway from zero to the first tick on the X axis (where the number is entered), or is the first tick 1,000 RPM?

Because the engine is operating FAR below the torque peak. You need to regear -- and since you mentioned future plans to lift and run larger tires, consider your choice carefully before acting.

If we're dealing in assigning "characteristics" on the basis of anecdotal observations ("I saw one like that last week and another one three years ago"), I'd say mid-80s Chevy pickups are MUCH more prone to suffering "characteristic driver's side sag" than MJs. Come on, people. The newest MJ around is 24 years old at this point. They ARE trucks. It's not realistic to criticize the design or construction when you're dealing with a truck that's two decades old and you have no idea who has been driving it or how badly it has been abused.

What is this "characteristic driver's side sag" to which you refer? Granted, I only own three MJs at the moment, but several others have passed through the Jeep farm, and I know a number of other people who own MJs. I've never once heard anyone complain about a "driver's side sag."

Looking for torque charts in response to the thread about towing capacity, I discovered that I don't seem to have any horsepower/torque charts for either the Renix or early HO 4.0L engines (or any of the 2.5L engines, for that matter). Worse, they don't seem to be available on the Internet. If any of you have any older Jeep literature that includes power graphs, I would very much like to get a scan or a photo so I can enter the data into a spreadsheet and create a set of graphs that are all the same size and scale so we can have them for comparison purposes. Ideally, I'd like graphs for the XJ or MJ -- I think the values are a bit different for the same engines in the YJ and TJ due to exhaust differences. But ... more data is better than less data, so I'll take anything I can get. If you have anything, drop me a PM and I'll give you an e-mail address to which to send it. Thanks

Agreed. And there is certainly the possibility that it's a 24-volt light. I'm going to be scrapping a couple of XJs this Spring. I can easily cut out a back-up light socket for you -- I don't have any plans to save the chassis wiring harnesses.

If you have the heater set to defrost, it still cycles the a/c, to dry out the air it blows at the windshield. Another possibility is alternator load, when the fuel pump kicks in and shuts off.

By "operational rev range" you are referring to the RPM range where the engine is producing maximum torque. Large diesels actually have a much broader torque range than that (it's a characteristic of diesels in general), but the trucks are equipped with multiple gears to keep the engine in the range right at the torque peak. That's what I'm saying also applies to the Jeep 4.0L. Ideally, for towing you would want to keep the engine close to the torque peak, which is 2400 RPM. If you're going to go off the peak, go for more engine speed because at least then your gaining horsepower in exchange for losing torque. When you drop down to 1800 RPM or less, you don't have either torque or horsepower working for you.

You may just need a new radiator pressure cap. The 2.5L has a conventional overflow catch bottle, not a pressurized surge tank like the Renix 4.0Ls. The coolant doesn't circulate through the catch bottle, and once coolant gets to the bottle no heat is added (except if more coolant enters). That means it can't boil in the catch bottle -- but if the temperature is above boiling (212 F) when it hits the catch bottle, it will boil because it's suddenly going from pressurized (at whatever your pressure cap is rated for) to atmospheric pressure. I believe the factory cap is rated to 13 psi, and that raises the boiling point from 212 degrees to somewhere around 240 or 245 degrees. If the pressure cap isn't doing its job, the coolant in the system will boil at a lower temperature, which will cause more of it to expand and to flow out into the catch bottle.

And at the cost of fuel economy.

An 18-wheeler has multiple granny gears to get the loaded rig rolling, and a fat torque curve that picks up at under 1,000 RPM. Big trucks are geared properly from the factory, and have enough gears in the transmission, to allow the driver to keep the RPMs in the fat part of the power band. The OP here is running the wrong gears, never approaching the torque peak on the highway, and then wondering why the engine feels like it doesn't have any power. The answer is simple -- because it doesn't have any power. To my amazement, I couldn't find an actual horsepower/torque graph for the early 4.0L engines anywhere on the Internet. They used to be everywhere, such that I never thought to download and save a copy. Now I'm really sorry. I was able to find one for a '99 version, here: http://www.automobile-catalog.com/wykres_power.php Note that the torque curve on this one is not as flat as for the Renix engines, and the torque peak is up at 3,500 RPM rather than 2,400 RPM. What is common for both, however, is that there's nothing happening below 2,000 RPM. In the graph, if we look at 1,800 RPM (65 MPH on stock tires with stock gearing), the torque is about 240 Newton-Meters (which is about 177 foot-pounds), and the horsepower is a mere 65 (or so) horsepower. I did finally find a copy of an earlier power graph, but it's so small you can't read it. For what it's worth, here it is: The torque curve is the upper, flatter line. The curve from lower left to upper right is the horsepower line. If we take the torque peak at 2,400 RPM, you can see that the curve is increasing up to that point, and becomes (relatively) flat only after 2,400 RPM. And, of course, as with the other curve you can see that below 2,000 RPM there just isn't a lot of horsepower being produced. That's why vehicles have tranmissions with multiple gears -- so you can choose a gear that matches the engine speed and power range to the amount of power needed to get the job done.

Automatics don't have manually (or "pedally") operated clutches. It's easy to slip a clutch and burn it out when trying to get started with a heavy load in tow.

There's a difference between towing capacity and engine performance, and it seems to me that the primary complaint in the original post here was about engine performance. Certainly, the stock 3.07 gear ratio that came from the factory with the 5-speed 4.0L trucks was a bad choice. You say you only want to tow 2,500 to 3,000 pounds, but that's more than the load capacity of even the metric ton option models, and if you get to 3,000 pounds it's nearly double the weight of the truck. You can't double the weight and expect the performance not to take a hit. The torque peak for the '89 4.0L engine was 2,400 RPM. Because of the axle gearing and the overdrive 5th gear, at any normal highway speed you're actually running below the torque peak in 5th gear. Assuming standard-ish tires, 60 MPH in 5th gear is only about 1700 RPM. You don't hit the torque peak in 5th until you're up to 85 MPH. To get the engine turning closer to the torque peak at sane towing speeds, you need to change your gearing. 3.73 would be a good choice, but not available in used axles that will fit the MJ. 4.10 is also a good choice, and was used in XJs and MJs with the 4-cylinder engine.

True. Unfortunately, I'm in one of those situations where I can't afford to live here and I can't afford to move.

Easier said than done, unfortunately. Connecticut hasn't allowed pull-it-yourself junkyards for more than 30 years. The chances of finding an XJ with a 242 that hasn't already been crushed are pretty unlikely.

Great. Awhile back I got a 242 transfer case, but I didn't think about grabbing the linkage or the shift gate because I didn't think they were different. Do you know if the 231 shift gate will work with a 242, or do I need to start hitting the junkyards?

Correct. The lever itself is basically just a lever -- it's a press fit into the multi-function switch. If your lever hasn't broken off, it's probably not the problem.

So did I. That's why I hated the KYBs -- they did just the opposite of what a good shock should for for keeping the tires on the pavement at speed.

I completely forgot about the TJ. My bad.

Check timing and distributor indexing.

I have used only Walker on my XJs and MJs for over twenty years.