Eagle

It isn't the abrupt torque that'll do the damage. In the 231, the front and rear driveshafts are locked in 4WD. That means they both spin at the same speed. If the rear wheels are under power and spinning when you shift, the rear wheels are rotating faster than the front wheels. When you try to shift, all you're going to get is a loud, alarming grinding sound. It's exactly the same as trying to shift a manual tranny without the clutch, and not matching the engine speed to the road speed. It's entirely possible to do it, but you have to be abusive. It is synchro'd, it is possible to shift it in a way you shouldn't. I have seen it happen, granted not actually on pavement, but in similar situations where the rear is spinning and "I'll just engage the 4wd" happens. And if you tear the synchros and the teeth off the annulus, that was still torque that did it. I disagree. If you tear up the synchronizer trying to engage 4WD, it isn't torque that does the damage, it's phyical abrasion/interference. If you can't get the 4WD engaged, you can't even begin to apply torque.

Donald -- Go to your room.

Why spend money to do something you can do for free?

http://comancheclub.com/topic/52487-before-i-order-injectors-are-they-definitely-bad/

I agree with Cruiser. My '88 XJ has the CAD. When did I realize that it didn't work? Right -- when I was trying to get to work in a blizzard, and could understand why I couldn't make it up the first hill on the way to the office. That was long enough ago that I didn't know how easy it is to just lock the CAD in the engaged position, so I bought a replacement vacuum harness for it. Now that I know, if I get the '88 on the road this summer (as planned), I will lock it and forget it.

Doesn't matter. It's just an ON-OFF switch that closes a circuit if there's a brake failure.

It isn't the abrupt torque that'll do the damage. In the 231, the front and rear driveshafts are locked in 4WD. That means they both spin at the same speed. If the rear wheels are under power and spinning when you shift, the rear wheels are rotating faster than the front wheels. When you try to shift, all you're going to get is a loud, alarming grinding sound. It's exactly the same as trying to shift a manual tranny without the clutch, and not matching the engine speed to the road speed.

If it was neutral safety switch it wouldn't crank. I think you need a CPS.

It means shift at any speed up to 45 MPH. (Although I thought it was 50 MPH.) Just checked -- the 1989 owner's manual says shift into 4-Hi "at any legal speed." They may have changed it depending on the year.

I'm pretty certain you are referring to part number 20 in the parts manual illustration. It's called a "reinforcement," not a spacer, and it doesn't go between the flex plate and the flywheel, it goes outside of (behind) the flex plate.

Way WAY back, pre-NAXJA, there was a guy on the old XJ forum by the name of Frank Swygert who ran an AW4 in an AMC Hornet (or Concord -- same animal). He controlled it with a single, 6-position rotary switch.

Are you replacing the flex plate, or changing to a manual transmission with a "flywheel"?

IMHO it's far easier to just remove the entire seat with the brackets than to try fumbling around underneath to remove the seat from the brackets.

The dash gauge never reads the same as an actual thermometer aimed at the engine.

Son, I was born in Texas. Don't live there now, but that's where I first saw the light of day. I know all about "good to go."

That's a "work-around," not a "fix." So you have a Renix. Do you have a tachometer with the small fuel gauge, or do you have the big fuel gauge to the left of the speedometer? I'm guessing that's what you have, because I don't think the small fuel gauge could rotate as far as the 5:00 o'clock position.

Sounds normal to me. Certainly not bad enough to be tearing the engine down.

If the brake fluid were being sucked back into the booster, I would expect the level to drop in the rear-most chamber (the one closest to the booster) rather than the forward chamber. My money is on a rusted/ruptured line over the fuel tank. I've had two of them go in that location.

The lower flange on those brackets (where the sway bar mounts attach) have slotted holes. Why not just move the brackets as far forward as they'll go?

^^^ This. Also, jack it up, remove the rear wheels, pull the brake drums and look inside for leaking wheel cylinders.

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Early in production of the XJ Jeep ran into supply problems with the AX5 and used the T5 as an alternate OEM part. I was under the impression that such problem were resolved before the MJ came out in 1986, but perhaps not.

I'd sell the '89 and keep the '86. That truck is beautiful.

Those pressures are within spec. The spec is 13 psi minimum at warm idle, and 37 to 75 above 1600 RPM. Newer 4.0L engines typically run 55 to 60 psi at highway speed, but as bearings wear you lose some. 40 psi isn't bad. My point in asking those questions was that pulling the head to replace the lifters is a lot of work, and on a higher mileage engine that may need a rebuild soon(-ish) it probably doesn't make sense. For a Jeep 4.0L 158,000 isn't high -- except that yours isn't 158,000, it's that plus however many miles the previous owner piled on when the odometer conveniently wasn't working. Figure 175,000 to 200,000. At that point, some lifter noise is normal and to be expected. I haven't heard your engine, so I don't know how loud it really is compared to other Jeep engines of similar age and miles. If it were mine, I think rather than doing any mechanical changes I would just switch to 10W40 or 5W50 (or 15W50 if you can't find 5W50) synthetic oil and keep driving.

But did you replace the fusible link with a fuse?