Geonovast

You can get one from www.rockauto.com About $55ish for a shortbed, $35ish for a longbed.

Did you do a toe alignment?

Probably wouldn't be a bad idea to change your U-joints to see if that's the problem.

4.0 swaps a lot of work, but pretty straightforward if you get an entire donor XJ. Even if you pick up a 4.0/5 speed XJ, I still recommend at least finding a 3.55 geared front to match your rear. 3.07 gears are crap.

I checked the 93 231 in the 2.5 MJ today. It does have a true neutral. I also checked the 90 242 in the shed. It does have a true neutral. Twoish years ago, when I tested an 88 231, it did not have a true neutral. Perhaps the T-cases paired with CAD axles aren't true? There's a 91 231 in my 4.0 MJ that came from a 91 XJ, however that XJ did have a CAD axle, and the T-case is equipped with the vacuum switch. I'll check that one, and the 88 XJ's 231s tomorrow.

No, all the seal does is stop fluid from coming out of the diff. If you have a mad vibration from your driveshaft, either your driveshaft is out of balance, one or both of your U-joints are bad, your pinion angles aren't right, or your pinion bearing is bad too. Were there any metal shavings in the fluid when you changed it?

Only the last few inches of the axleshafts are past the seal. Seals are almost inside the diff. There's no point in lubricating the entire shaft.

Make sure the truck cannot move before you loosen and tighten that nut.

5 speed/242 is fine, just was never offered from the factory, I would assume because having a manual transmission isn't "luxury" enough.

It could be causing your injector to not function properly, as well as sensors such as the CPS to not function if it's overheating. Sounds like you have a cooling system to fix first, or a leaking injector will be the last of your worries.

You can't disconnect it at the transfercase without popping it off the axle first. And no, it cannot spin if it's not connected to the axle.

I am going to go test this again on a 93 231 tomorrow.

The U-joint is held to the yoke with two straps that are each held on with two bolts that have a 8mm head. You need an 8 mm wrench to remove the rear shaft. You'll either need to simply tie up the shaft under the bed, or slide the shaft out of the transfercase, and lose all your fluid, or somehow seal the end of the case so you don't lose any fluid. Also make sure you wrap the U-joint with electrical tape so the two now free caps don't fall off. This is a front axle, but it works the same. You can see where the 4 bolts are, remove them, take off the straps, and you'll probably have to shove a prybar between the U-joint and the pinion nut to pop it out of the yoke. Be careful not to pop the caps off.

IIRC, 39-41 is good at idle. My 2.5 acted like that when the pump went out. I could drive it, although not very wheel, through all the gears, but a fuel pressure test read 13 psi, when it was supposed to be the 39-41. Granted, that was 4 injectors, not 6, but still. First thing you should do is test fuel pressure.

You need a press to get the gears on, and a good gear puller to get them off. Don't lose any of the tiny little synchro keys and springs, and you should be fine.

Get ahold of a fuel pressure tester first. If you get a good reading at the rail, then it's not a pump problem. You can get the pump out without dropping the tank, but I highly suggest dropping the tank. Getting it out isn't the issue, getting it back in and everything to seal correctly is a PITA with the tank in the truck. First time I pulled a pump, I did so without dropping the tank. The whole winter I couldn't fill it up past 3/4, or it would leak. In spring I dropped the tank, reset the pump, and it was fine. I believe I spent less time dropping and installing the tank, than I did trying to set the pump in it using the driveshaft as a pillow.

Pop apart the AX-5 and see what's going on. Yes, you could combine them to make a 4wd AX-4, but why not just keep it a 4wd AX-5? There's no sense doing all that work to it, just to rip it apart again to add 5th when you could have done it before. If the 5th gear dogs too much with 3.55s, just don't use it. AX-4s are IDENTICAL to the AX-5 except for the presence of the 5th gear on the output shaft, the 5th gear stuff on the layshaft, presence of the 5th slider, and the reverse sliders are different.

So you don't want the 5 speed because you don't like shifting? Ok. I was just wondering if you wanted the auto solely for the cruise.. because sticks can have cruise. (you don't have to downshift for lights)

Why do you not want the 5 speed? Speedo is not a problem. Unscrew the electric sender on the trans. The housing that holds the speedo gear is the same for the electric and the cable. Once you remove the electric sender, your cable will screw right on.

Probably the first question that should have been asked.. Is it an auto, or a real transmission?

Check your fuel pressure, could be starved for fuel.

Shouldn't be all that hard, would be if you were looking for one with an auto.

Replace your battery cables and terminals. Jiggling the pos battery cable to get it to start... obviously there's something wrong with the cable.

So, they're just gonna kick us back to the last version, cause that one worked, right?

Do you have a full gauge cluster? Do you know how hot it gets when it runs?