How durable are the factory TJ Rubicon lockers?

[Mumblewood]

Most of my friends broke their rear lockers within 5 years, I try most stuff unlocked first and try not to let it hop so mine lasted considerably longer, but did eventually break. We are all running either Detroit’s or ARB’s rear now but all still have the factory front lockers I think

 

[LieutenantJohnson]

I threw a front Rubi locker in the rear of mine last year when my rear LSD bits broke apart in the rear Rubi locker.

No issues yet in 5months running an LS motor. Just waiting for the day it dies and I can swap in an ARB 33 spline.

 

[Jerry Bransford]

The fix that comes to mind is to have the rear axle's nipple brazed to the axle which would stop that particular leak. Maybe packing JB Weld around where the nipple seats in the axle housing would fix that leak too. The Rubicon's locker engagement logic is convoluted enough so I don't know if the front locker's flashing light indicating it's not locked has anything to do with the rear locker's problem or not.

Personally I completely rewired both of my Rubicon's lockers so they're controlled by individual on-off switches. I didn't like how they were not independently controllable not to mention the switching circuit wasn't working properly when I acquired my present TJ.

So far as the TJ Rubicon's lockers go, they're reliable so long as you're not engaging them at stupid times like when your tires are spinning. Mine are 16 years old and they're still fine despite their use on occasionally very tough rock crawling trails. That a particular group of wheelers isn't getting more than 5 years out of their Rubicon lockers makes me suspect how they're being engaged.

 

[one100bill]

Easy to replace the axle vent nipple? Do I need to remove the differential covers? Anyone done this before?

 

[AndyG]

Have you guys ever heard Rubicon lockers are Japanese made? I read that once.

 

[L J]

Have you guys ever heard Rubicon lockers are Japanese made? I read that once.

they are or rather were

 

[Jerry Bransford]

Have you guys ever heard Rubicon lockers are Japanese made?

They were, they were made by Tochigi Fuji Sangyo.

I was told that by Jim Repp in a phone conversation I had with him in early 2002 before the TJ Rubicon was released for sale. Jim was Jeep's senior engineer at the time and is credited with being the driving force behind the creation of and the "father of the TJ Rubicon".

 

[jjvw]

In the late 2000's GKN Driveline bought Tochigi Fuji Sangyo. Several years ago I contacted GKN trying to identify what other vehicles on the international market used the same lockers as the TJ. The people I emailed with had no knowledge of the acquisition and the Mopar part numbers we know are meaningless to them.

Point being, if we were ever to find another vehicle with the same Tochigi Fuji Sangyo lockers somewhere else in the world, we probably need to know Tochigi Fuji Sangyo part numbers, hope that GKN still has those records, and that they care enough to search for us.

It wasn't the long ago that we discovered that KIA and Suzuki used the same low pressure pump as part of the driveline disconnect on some of their vehicles. So it would not surprise me it's there is some weird Asian market utility truck with "Rubicon" lockers running around out there.

 

[AndyG]

They were, they were made by Tochigi Fuji Sangyo.

I was told that by Jim Repp in a phone conversation I had with him in early 2002 before the TJ Rubicon was released for sale. Jim was Jeep's senior engineer at the time and is credited with being the driving force behind the creation of and the "father of the TJ Rubicon".

I think he's the guy there is a great interview on about the project on YouTube I found...I haven't been able to find it again but it was just fascinating how intrepid they were on what they felt was needed for rocks and better off-road performance.

 

[Jerry Bransford]

I think he's the guy there is a great interview on about the project on YouTube I found...I haven't been able to find it again but it was just fascinating how intrepid they were on what they felt was needed for rocks and better off-road performance.

That's him, that video was a fascinating story about how the TJ Rubicon came to be. He had actually contacted me to ask me about a chronic misfire problem I had posted on several Jeep forums on my then new '97 TJ. At that time they didn't know it was caused by a bad batch of valve springs and he sent me a big box full of parts to try since the problem was happening across the country. Cool guy, we had phone conversations over the years after that especially in the time period before the Rubicon hit the dealers. He was "leaking" information to selected Jeepers in an effort to keep some of the false rumors down and one of them was about its locker which he filled me in on.

 

[AndyG]

That's him, that video was a fascinating story about how the TJ Rubicon came to be. He had actually contacted me to ask me about a chronic misfire problem I had posted on several Jeep forums on my then new '97 TJ. At that time they didn't know it was caused by a bad batch of valve springs and he sent me a big box full of parts to try since the problem was happening across the country. Cool guy, we had phone conversations over the years after that especially in the time period before the Rubicon hit the dealers. He was "leaking" information to selected Jeepers in an effort to keep some of the false rumors down and one of them was about its locker which he filled me in on.

That is so so cool.

I don't have years of off-road 4 by 4 experience... And getting out and seeing what a Rubicon can do with lockers has just absolutely blown my mind.

I've been climbing a pretty nasty section close to home and I went down there at night when it was wet and snowy recently with a guy who would be closer to your end of the spectrum in the off-road world than to my end-

I told him I didn't think we could climb it wet..he said sure you we can and you haven't beat on this thing at all

It has rock or two on the hill that are like tombstones

Sure enough ... we were able to climb it. .. I am just amazed.

 

[jsloan601]

My mechanic says my rear locker has too much play in it and needs to be replaced. So, from what I am reading here, my best bet would be to get a front locker and put in there?

 

[Steel City 06]

My mechanic says my rear locker has too much play in it and needs to be replaced. So, from what I am reading here, my best bet would be to get a front locker and put in there?

If you can find it, it would be a great low cost bolt-in solution. Either a front or rear should be fine.
If you use it aggressively, it may be worth switching to something aftermarket like the new Elocker4 or the ARB. Either of those would require new wiring or plumbing.

 

[jjvw]

Don't put a front Rubicon locker in the rear. The spider and side gears are barely adequate for the front.

 

[Jerry Bransford]

Don't put a front Rubicon locker in the rear. The spider and side gears are barely adequate for the front.

They're not the same??? I know the lockers are different but I would have guessed the spider/side gears were the same.

 

[LieutenantJohnson]

They're not the same??? I know the lockers are different but I would have guessed the spider/side gears were the same.

Nope. Absolutely not haha. The rear uses helical gears and 4 pinion and the front locker uses a 2 pinion spider gear setup.

The rear is stronger BUT has the limited slip in it as a weak point. If you keep it locked as soon as you hit dirt, you may be okay. If you 2wd it on FSRs and like go fast on corners, it won't last

 

[LieutenantJohnson]

Top pic is the limited slip gear toasting in the Rear Rubicon locker

Bottom 2 pics are my 2 spiders inside the Front locker (which I put in the rear) that decided to crap

 

[Brianj5600]

Do the spider gears carry load when locked?

 

[Grant Lasson]

The LSD is what caused my rear to fail--not the locker. Gear-driven LSD and the gears failed. Could easily be because of hard use but I wheeled a lot in 2WD in the Utah desert/plains.

I wouldn't want another LSD/locker combo.

 

[jjvw]

Do the spider gears carry load when locked?

No. But most spend the majority of their lives unlocked. And most people like to lock up after getting stuck, so the front gets plenty of use while open.