Transfer Case "Tera-Low" Issue, Advice Needed

Beachhead

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Chico, CA
Awhile back my Transfer Case started developing a swishy sound, and there were aluminum particles in the fluid, so after several months I finally got around to taking it off.
Took it to a shop to have it looked at and rebuilt, and he informed me it was not a factory 231 transfer case, but instead a 4:1 Tera-Low kit on the front half. Which he says are known to be unreliable, and of which parts are no longer available.

He says he may be able to find some used parts and fix it, or replace the whole thing with a factory transfer case.
It looks like online remanufactured cases are a lot of money, upwards of $1k and i'd like to not sink a whole lot more money into this thing but i'm not sure what to do.

What is the best thing to do here? I was not aware this Jeep had this aftermarket transfer case or why it was put in.

Thank you.
 
Lots of stock cases in decent shape on FB. Try to get one from a same year TJ with the same engine/transmission if you can. Others will work, but you'll need to search a little to find the compatibility. Has to do with the input shaft length and spline count. You can find them for $150-$200 all day long. If they don't sound like a box of rocks, chances are it's fine.

Then take your old case and rebuild it OEM style so it's fresh and ready to rock when your new/old one shits the bed. Don't let your mechanic "throw out" your old case. Keep it for parts. Maybe you get lucky and the terra low kit isn't the issue. I'd love to get my hands on one of those despite their rep.
 
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Awhile back my Transfer Case started developing a swishy sound, and there were aluminum particles in the fluid, so after several months I finally got around to taking it off.
Took it to a shop to have it looked at and rebuilt, and he informed me it was not a factory 231 transfer case, but instead a 4:1 Tera-Low kit on the front half. Which he says are known to be unreliable, and of which parts are no longer available.

He says he may be able to find some used parts and fix it, or replace the whole thing with a factory transfer case.
It looks like online remanufactured cases are a lot of money, upwards of $1k and i'd like to not sink a whole lot more money into this thing but i'm not sure what to do.

What is the best thing to do here? I was not aware this Jeep had this aftermarket transfer case or why it was put in.

Thank you.

The mechanic is correct that they are no longer manufacturing the Tera Low and that parts are hard to come by. They are only unreliable when they are treated contrary to the manufacturers recommendations which state that you should not run it over 2,500 for more than brief moments of time when in 4L and 4th or 5th gear. This is due to the high rpms of the planetary gears in the Tera Low.
 
The mechanic is correct that they are no longer manufacturing the Tera Low and that parts are hard to come by. They are only unreliable when they are treated contrary to the manufacturers recommendations which state that you should not run it over 2,500 for more than brief moments of time when in 4L and 4th or 5th gear. This is due to the high rpms of the planetary gears in the Tera Low.

Installed a Tera Low kit in my '98 XJ with AX-15 and 4.56s almost 20 years ago and spent most of that time Rock Crawling in Moab enjoying a >70:l crawl ratio.
During that time I never had a problem with the transfer case, but I did make sure to change the Redline ATF yearly, tried not to over rev the transfer case and I installed a fuel filter on the vent line as a mist accumulator.
 
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Installed a Tera Low kit in my '98 XJ with AX-15 and 4.56s almost 20 years ago and spent most of that time Rock Crawling in Moab enjoying a >70:l crawl ratio.
During that time I never had a problem with the transfer case, but I did make sure to change the Redline ATF yearly, tried not to over rev the transfer case and I installed a fuel filter on the vent line as a mist accumulator.

Great little units if you use as designed. Mine is still going strong. No substantive complaints. Sometimes I wish I had more wheel speed in 4L, but other than that it’s great. 81:1 crawl ratio with the manual. Now that I auto swapped IDK what the ratio is, but not as concerned.