Chasing 231J leaks

Sounds like the pumps not working and the case is cracked, but your symptoms are pretty weird and still questions remaining.

Agreed but I don't know what other temperatures folks have on 231s. I have a data set of 1.

Hard to make good conclusions without a data set.

Guess it's time to fire the parts canon.

Anyone have a good source for a new front yoke? All the ones I find say they're YJ only to 95.

-Mac
 
Drove ~500 miles up to Washington and back. Clipped pig mats under the transfer case and added 1/2 to 3/4 quart of ATF, and changed out the soaked pig mat and wiped up stuff that sprayed off the front driveshaft.

Fill plug was ungodly hot.

Made it to our campground just outside Yakima, WA Thursday night. Made camp, spent the night...swapped out the soaked pig mat, etc etc in the morning.

We drove 50 hard miles that day...40 was pretty rough...4-5 level trail, tons of dust... almost all in 4 low first gear. Checked the pig mat twice during the day and again when we got back to camp around 8 pm.

Dry. Not a single leak. Pulled the fill plug and ATF came out... slightly overfull as I had left it. What the hell?

Drove all the way home today. Didn't check the level when filling up. Pig mat soaked. ATF dripping on the shop floor.

Took the IR gun to the case...most of it was 200, but the center and tail shaft were 220 to 230 degrees.

As an aside I checked the cat...200 before, 380 after...90 degrees on the aluminum skid underneath. When wheeling I left a 3L water bladder on the passenger floor and took a warm shower when we got back to camp...going to get a shower bag and do that more often.

So, no clue what's going on. Going to let things cool off and pull it again tomorrow and see if I can use this 92/93 front case half to replace the front. Also going to replace the front yoke...maybe it's out of round and distorting the seal.

Magic trail dust is the only possible explanation.

@Wildman was talking about PNW companies that make a D300 case and I believe he called it a bare/bear box. Suggestion was double 2.72 ratios for both paired with my AX-15 and 4.88s.

Anyone have links or names of the companies? Behemoth is an option but I want to explore PNW sourced parts first.

View attachment 629884

-Mac

Hey,Mac,I think I would get a different case and have it rebuilt,and just be done with it?
 
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Agreed but I don't know what other temperatures folks have on 231s. I have a data set of 1.

Hard to make good conclusions without a data set.

Guess it's time to fire the parts canon.

Anyone have a good source for a new front yoke? All the ones I find say they're YJ only to 95.

-Mac

I found a new old stock not too long ago, but regardless you want 4798120. The YJ yoke is a traditional style with straps and not CV/double cardan style, so you for sure don’t want that.

Crown makes one for the TJ application, but it won’t have the dust shield. I bought an Omix one first that did have the dust shield, but the yoke was made a bit differently which pushed the dust shield towards the transfer case and the shield rubbed the case. So that one was no good unless I removed the dust shield which was the whole reason I bought that one to begin with.
 
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Hey,Mac,I think I would get a different case and have it rebuilt,and just be done with it?

I have a 92/93 case. I think I only need the front half. I think I need to move everything from mine to the new case front including the front flange and planetary.

I don't know if the vacuum switch hole on the 92/93 case is the same as the switch on the 96/97 case.

These are the parts I think I need...a yoke on the crazy assumption mine is out of round or something killing the seal. A pump because I think (but don't know) it's hot and maybe that's causing the issue (but works perfectly otherwise). Bearing and seal kit. The 92/93 case wasn't sealed and I want to replace any front case bearings. The kit gives me options.

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I PMed three people with complete cases yesterday and nobody answered.

Not sure anyone has made...but I can't find a complete guide to 231J years and intercompatibility.

Generally speaking most research I've done seems to indicate a break somewhere between 95/96 with planataries and vacuum switches.

-Mac
 
Oh and the rusted Sahara has I think a 242 part time case. I suppose I could use the front case half and yoke off it. Just lothe to rip it apart.

-Mac
 
My thought is the TCsse ATF stays cooler during off-roading because we’re going so slow and parts are moving slow. Fluid being jostled around. But when you get on highway all that changes. Parts moving fast. Pump really needed because no jostling around. Getting much hotter. I bet that pump is done. The little O-ring is there, right?

Man I wish I had kept that full case for you. It would have been a straight swap if yours can take the short snub.
 
I have a 92/93 case. I think I only need the front half. I think I need to move everything from mine to the new case front including the front flange and planetary.

I don't know if the vacuum switch hole on the 92/93 case is the same as the switch on the 96/97 case.

These are the parts I think I need...a yoke on the crazy assumption mine is out of round or something killing the seal. A pump because I think (but don't know) it's hot and maybe that's causing the issue (but works perfectly otherwise). Bearing and seal kit. The 92/93 case wasn't sealed and I want to replace any front case bearings. The kit gives me options.

View attachment 630060View attachment 630061

I PMed three people with complete cases yesterday and nobody answered.

Not sure anyone has made...but I can't find a complete guide to 231J years and intercompatibility.

Generally speaking most research I've done seems to indicate a break somewhere between 95/96 with planataries and vacuum switches.

-Mac

Your later model planetary will not work in that transfer case since that transfer case is a 92-93. They changed it right at the start of 95. I have a 95 YJ case built in October of 94 and it uses the TJ stuff (late model planetary), I also have one built in 93 for a 94 YJ and it has the old parts. So the change happened sometime between then. Officially, the 95 YJ FSM notes new parts, so I think changes were officially for the 95 model year, regardless of date built.

Vacuum switch and electrical switch are interchangeable, no issues there.

I haven’t figured out why, but the annulus gear inside the t-case front half appears to be the same early or late. Yet I tried a late model input gear and planetary into an older front case, and it made bad noises when I spun it by hand.

Luckily, since you have an AX15, you can use any length 23 spline input. So if you do need to buy one for the YJ case, your options are opened up.

Aside from the planetary differences, you can definitely make the YJ case work in your TJ. The factory front yoke will be fine so long as you get the TJ style seal (4798112), and the SYE will fit too. You can keep the synchro hub parts from the YJ case or use the more simple non synchro parts from the TJ case. Doesn’t really matter. If you keep the YJ hub and sprocket (slightly smoother shifts due to synchro), then you will need to hammer out the caged needle bearings to fit them onto the SYE mainshaft.
 
Well, then tell me what pistons, rings and crank and rod bearings should I be shopping for?

I know DeXJs sells used piston sets. I have a press...so that's not an issue.

Behind door two is a 160k mile used 4.0 and 32rh with factory cruise control sitting in my yard. I am half tempted to yank the harness, HVAC box, controls, steering wheel and complete engine and PCM.

But it's a complete unknown. I think before I exercise door two two...

Option C - stroker kit...

-Mac

Dex also has new piston kits. Or you can send him your arms and he will install new pistons. Since you have a press, I would order new pistons and rings from him.

Don't forget...this can be done without pulling the engine.
 
Where?

Here's another option...pay for a Copart membership and buy a wrecked Rubicon.

Hell I probably could drive my Jeep to Utah to pick it up. Remove the T case in the parking lot and scrap the rest.

https://www.copart.com/lot/56426375/salvage-2006-jeep-wrangler-tj-rubicon-ut-salt-lake-city

-Mac

Mac. Because you would be buying a motor vehicle you must be a dealer. The good news is there is a list of people on their website who are dealers who will place your bid for you - for a small fee.

Buying wrecked for parts stockpile is a smart move. A while ago I let people know about a running 04 that got rain water inside the vehicle and it sold for $750. The entire rust free running TJ.
 
Damn I thought it was from a 98. So this isn't any different than the 92/93 case. Grr.

-Mac

XJs got rid of the CAD and vacuum switch around 1990, carrying I think a bit into the 1991 year until they finally stopped. So it’s at least that old. I’m pretty sure I see a “90” on the tag, indicating it was built in 1990. I would rather have the YJ case than that one, personally.

Any of them will work for what you’re doing, you just need them to be 23 spline to fit your transmission.
 
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Agreed. And it's complete enough I can clean it up and resell the one I just bought.

Swore it was from a 98 TJ.

Will the YJ vacuum switch hole work with the TJ 4x4 switch?

-Mac

If it was from a TJ, the main shaft would be exposed, there wouldn’t be that extension housing tail cone piece. Only the 96 and older XJ and 95 and older YJ used that piece.

Yes, the vacuum switch and electrical switch are the same thread and they interact with the sector plate or mode fork rod the same; aka they are interchangeable.
 
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