Eagle

The fuse for the aux fan in the 2000 XJ (the new style fan) is a 40-amp fuse. Not surprising you're popping fuses like Chinese lady crackers on the 4th of July if you're trying to spin that baby through a 20-amp fuse.

WHY would you do this to a daily driver, especially since you already ruined one truck? Yes, that's too much tire for a 2.5L with stock gearing. By definition, daily drivers see a lot of pavement. Serious rail rigs are NOT suitable for daily driver use, and often aren't safe for daily driver use. And you might be surprised just how capable an MJ is running on 31s with a budget boost.

Isn't the '99 WJ head a 1-1/2 DIN size? Or maybe double DIN? The XJ/MJ is single size. I don't think the WJ head will fit the space available for it in the MJ.

Well, you didn't mention in your post that you want to convert from the old trim to the new trim. The new gasket is trim -- the windshield itself is the same part -- but you do have to remove the glass to install the new style gasket.

Who "asserted" spinning it near redline? I wrote that maximum efficiency is when you cruise at the torque peak ... nobody said anything about the horsepower peak. For the Renix 4.0L, the torque peak was at 2400 RPM and the horsepower peak was at 4750 RPM. Highway cruise at around 2400 to 2600 RPM is, as I wrote, right in the "fat" part of the torque curve for the engine. Basically, yes it does. In fact, the working definition of torque is "horsepower per revolution," so the torque peak IS, by definition, the RPM at which the engine itself is operating at maximum efficiency. As has been noted, exponential increases in various drag factors as a function of vehicle speed enter into it and cannot be ignored, but the simple fact is that a highway cruise that's almost 1000 RPM below the torque peak (like the way the 5-speeds came from the factory) cannot deliver optimum fuel economy in the real world. As proven by the fact that my '88 Cherokee gets as good mileage in 4th gear on the highway as it does in 5th.

There is no gasket. The windshield is held in and sealed with glass sealant. Used to be a butyl, but I think now they use a polyurethane formulation.

Forget what those charts say -- they're wrong. I bought my '88 Cherokee new. 4.0L 5-speed, so it came with (and still has) 3.07 gears. Original tire size was 205/75-15s, but I've been on 225s or 235s (depends on what set I have handy) for many years. I'm in Connecticut, so we don't have long stretches of 65 to 70 MPH highway. Typical highway cruise is about 60. And at that speed I get better gas mileage staying in 4th than when I use 5th. Years ago, I determined that I'd be better off running 3.73s. But then I got the '88 MJ, with 31" tires and 3.07 gears, so the new gears went into the MJ and the XJ stayed stock. You gents are forgetting two things: First, both the XJ and the MJ are "boxes on wheels." Aerodynamic drag increases exponentially with speed. The fact you get worse mileage at 70 than at 60 is not due to engine RPM, it's due to increased drag and there's not a damn thing you can do about that other than drive slower. I had the same thing with the 1999 Grand Cherokee I owned. That was with the newly-designed 4.7L V8. On a trip from CT to wstern PA (about 500 miles) I logged about 19 MPG on the way out, cruising at 70. On the way back, I had plenty of time so I set the cruise for 60 and I got 22 MPG. The other thing you forget is that the base engine on which the 4.0L is built was originally designed by AMC back in 1963, first appearing in the 1964 Rambler. Overdrive was extremely rare back then, and a standard transmission was a 3-speed. AMC was noted for building economy cars. Standard gearing was 3.08, with small tires. The typical gearing resulted in 2500 RPM at 60 MPH. That meant that a 72 MPH cruise speed ran the engine at 3000 RPM. Toady, you lads consider those engine speeds as excessive, but that's what the engines were designed for, and they would last 300,000 miles as long as you changed the oil. My old Rambler American used to routinely deliver 28 MPG set up like that. Of course, it was lighter in weight than an MJ, and we didn't have gasoline diluted with ethanol. But that's the engine speed range that's going to deliver the best economy. 3.07 in today's XJs and MJs was not selected because it's best for any real world purpose. They used that ratio because it generated good results on the unrealistic Federal mileage tests. Seriously. With stock tires in 5th gear and running 3.07 axles, 70 MPH is 1960 RPM. That's several hundred RPM below the engine's torque peak -- and several THOUSAND RPM below the torque peak for the HO engine. You can't deliver optimum economy running well under the torque peak.

Run the 215s until they wear out, then move up to 235/75s. The 235s are almost exactly the same diameter as 30x9.50s. With 235s behind an AW4 you'll be turning about 2200 RPM at 60 MPH and 2580 RPM at 70. That puts your cruising RPM right in the "fat" part of the torque curve, and that's where you want to be for maximum efficiency.

Looks pretty much Olive Drab to me.

Your links don't work for me, but if that's the Wilwood adjustable proportioning valve, it does NOT replace the stock distribution block in the front. The Wilwood is plumbed into the single line from the front block to the rear axle, downstream from the front distribution block.

Yes, you will. And the 84 tach does not have the adjustable potentiometer, so it has to match the cylinder count in your vehicle.

If you use a stock XJ floor shift or that one in your link, there won't be any cable up to the dashboard or steering column. That was only for MJs with the column shift auto. If you mean the cable for the steering wheel lock, your manual tranny column has a push button for that function. You can run a cable to interlock the steering lock to the shifter -- or you can ignore that and continue to use the push button as you have been.

Nope. The steering shaft is the same, only the box is different between manual and power steering.

Yes, the '90 cluster has the adjustable tach.

Who knows? It sounds like they bought it with the lift, so they have no idea. Maybe it's actually normal but they're used to Fords and Chevvies with push-button 4WD. Or ... whoever did the lift might have installed a transfer case drop and messed up the linkage.

I don't think that location is better -- I think it's worse. That would put one speaker right next to your left ear, with the other three all several feet away. Doesn't make sense to me.

Theoretically -- and actually -- the caster angle changed, and caster is an important factor in keeping death wobble at bay. That said, if it starts at 50 to 55 MPH, the underlying cause is tire balance.

The dealer-installed air wasn't wired the same as factory air. I have the dealer air in my '87. It's completely different from the OEM air in my '88 XJ and '88 MJ. Since you're taking the a/c from an XJ of the same year, you shouldn't need a diagram -- just move eveything from the donor XJ to the MJ exactly as it was set up in the XJ.

First, does the truck have a 231 transfer case with the central axle disconnect, or does it not have a disconnect?

That depends on whether you use a short (half-length) AAL or a full-length AAL. A full-length doesn't make the ride significantly stiffer/harsher at all, and if your springs are weak and/or saggy, a full-length AAL will probably feel like it rides better, not worse.

If he put on a spare that doesn't match the other front tire, that could account for a pull. Might be a different size, might be a different tread, might be running too soft or too hard.

Put those 5 back where you found them and follow the instructions I posted. You can see the screws I described in the diagram I posted -- that's why I posted it.

Are you asking about a replacement for the stock pull handle, or are you looking for some kind of key lock to immobilize the handle?

The basic engine is the same, but your '89 has throttle body injection and an ignition system from a consortium of Renault and Bendix in Europe. In 1991 Jeep switched over to using a Chrysler-engineered multi-port injection system on the 2.5L engines.

What type of mirrors, and what five screws? If you have the most common mirrors, which are the rectangular ones that mount to the front triangle of the door vent windows, you start by popping the retainer clips to loosen the interior door trim panel. Lift it up to clear the window channel, then either slide it back a couple of inches or let it drop down. This exposes the interior mount for the mirror. There should be (IIRC) one screw, at the bottom, holding the plastic trim piece on. Remove that, and you'll find three (3) screws holding the mirror itself. I stole this from another thread about mirrors: