Rubicon Locker Replacement

[That'll Buff]

Just got done with my first Moab trip, came out with a lot to fix. Main thing being that my rear limited slip on the stock locker finally let go. I always lock the rear the whole time I'm off-road, but after coming off Hells Revenge today it felt like the rear end was locked on every turn. I unplugged the airline leading to the rear pump to make sure the air was absolutely out, so I highly doubt the locker itself is engaged, and one or two turns were accompanied with a loud bind and bang, which I've read is a symptom. I think I read somewhere on here that the front locker bolts into the rear without any modification and means you don't run into the same issues with the lsd, am I right in thinking that? Planning to buy a front carrier from Rubicon Ressurection if so and put it in since it's much cheaper than going to something like ARBs. Also, if there is no limited slip, does that mean I don't have to lock the rear the moment I touch dirt anymore? Because that would be really nice.

 

[jjvw]

If you want no more concerns with the small Rubicon lockers, the ARB rd117 will accept the existing 513 thick cut ring gear.

I ruined two factory Rubicon rears. First one stripped the locker. The second one stripped the LSD and behaved like a locker. That second failure led to a rear ARB. I didn't bother putting a front in the rear because it is still an undersized locker and I never liked how noisy and sloppy my front one was the entire 120k miles I ran it. Eventually for peace of mind, I changed the front to an ARB, as well and never looked back.

 

[That'll Buff]

As much as I'd love to have the peace of mind, main thing is trying to get it back on the road while still living on a bit of a budget since I haven't started my job yet. Can't stomach dropping $1300 plus the cost of a compressor just yet is the main thing. Tough spot I know. As for the noise, I haven't noticed mine when I lock the hubs, although I haven't driven highway speeds with the hubs locked since I installed the axles. From the sounds of it though it would work putting a front carrier in the rear? I'd just like to not have to worry about the lsd again.

 

[mrblaine]

As much as I'd love to have the peace of mind, main thing is trying to get it back on the road while still living on a bit of a budget since I haven't started my job yet. Can't stomach dropping $1300 plus the cost of a compressor just yet is the main thing. Tough spot I know. As for the noise, I haven't noticed mine when I lock the hubs, although I haven't driven highway speeds with the hubs locked since I installed the axles. From the sounds of it though it would work putting a front carrier in the rear? I'd just like to not have to worry about the lsd again.

The front is a much weaker version of the rear locker even without a limited slip.

 

[That'll Buff]

The front is a much weaker version of the rear locker even without a limited slip.

How so? I'm not to familiar with many of the details, especially between the differences between the front and rear so now I'm curious.

 

[jjvw]

How so? I'm not to familiar with many of the details, especially between the differences between the front and rear so now I'm curious.

A clue lies in the factory thick cut 4.10 gears. The TJ Rubicon lockers were manufactured by a long defunct Japanese company, existed on the international market before the Rubicon ever existed, and were intended for a 3.92 and numerically lower standard cut gear set. That suggests a smaller tire than what the Rubicon rolled off the assembly line with. And possibly also a lighter vehicle than the TJ.

 

[That'll Buff]

A clue lies in the factory thick cut 4.10 gears. The TJ Rubicon lockers were manufactured by a long defunct Japanese company, existed on the international market before the Rubicon ever existed, and were intended for a 3.92 and numerically lower standard cut gear set. That suggests a smaller tire than what the Rubicon rolled off the assembly line with. And possibly also a lighter vehicle than the TJ.

That makes sense enough to me for the general lockers, but doesn't explain the difference in strength between the front and rear. It's likely something obvious I'm missing there, but it's been a VERY long few days...

 

[Ashim]

Many years ago my rear OEM locker failed. At the time, general opinion was to replace it with a front locker. Eventually it failed. Replaced with ARB, still running strong. When you see the front locker next to an ARB you'll see how much beefier it is. Spend the money now and go for the ARB.

 

[mrblaine]

How so? I'm not to familiar with many of the details, especially between the differences between the front and rear so now I'm curious.

I am not intimately familiar but I have a gear guy who is. Many years ago when the rears started failing due to the LS problem, we figured we'd be smarter than everyone else and circumvent the high cost of an ARB. I fetched up a front and took it with a rear axle over to him to get it installed and while polite about it, he basically told me I was a dumbass for trying it. He showed me the difference and mainly focused on 2 things, it wasn't really designed to be a rear locker and the pinion gears showed why.

Since then, we have encouraged many folks not to make our almost mistake. Several have viewed the messenger as either someone to be ignored, or did it out of spite. The brave ones have come back and said they should have listened. The chickenshits have not come back to admit their error here but we see them other places relate that there was a failure.

 

[jjvw]

I am not intimately familiar but I have a gear guy who is. Many years ago when the rears started failing due to the LS problem, we figured we'd be smarter than everyone else and circumvent the high cost of an ARB. I fetched up a front and took it with a rear axle over to him to get it installed and while polite about it, he basically told me I was a dumbass for trying it. He showed me the difference and mainly focused on 2 things, it wasn't really designed to be a rear locker and the pinion gears showed why.

Since then, we have encouraged many folks not to make our almost mistake. Several have viewed the messenger as either someone to be ignored, or did it out of spite. The brave ones have come back and said they should have listened. The chickenshits have not come back to admit their error here but we see them other places relate that there was a failure.

The pinion gears were always noisy and sloppy on my front. Early on, I was able to look inside while spinning the tires and saw a lot of excess movement. And there are only two pinion gears. I quickly learned about ARB lockers and saw how well fitted they are along with the four pinion gears and knew that was going to be a future replacement for the Rubicon stuff.

 

[Weasellee]

If needed. I have a factory front locker I’d sell you. Make an offer plus shipping. Definitely worked when removed.

 

[That'll Buff]

I am not intimately familiar but I have a gear guy who is. Many years ago when the rears started failing due to the LS problem, we figured we'd be smarter than everyone else and circumvent the high cost of an ARB. I fetched up a front and took it with a rear axle over to him to get it installed and while polite about it, he basically told me I was a dumbass for trying it. He showed me the difference and mainly focused on 2 things, it wasn't really designed to be a rear locker and the pinion gears showed why.

Since then, we have encouraged many folks not to make our almost mistake. Several have viewed the messenger as either someone to be ignored, or did it out of spite. The brave ones have come back and said they should have listened. The chickenshits have not come back to admit their error here but we see them other places relate that there was a failure.

That makes enough sense. I did some more digging last night and found the thread I got the original idea from by @Chris in 2016. What I hadn't done before I made my thread all 7 pages where they eventually talk about how they're weak due to the 2 pinion design. Funnily enough, you look up 2 pinion diff vs 4 pinion diff and one of the first results is a broken 2 pinion diff out of a land rover, so I guess that settles that debate. Looks like I'll have to be part of the buy once cry once crowd.

 

[That'll Buff]

If needed. I have a factory front locker I’d sell you. Make an offer plus shipping. Definitely worked when removed.

Thanks for the offer, but I think I'll bite the bullet this time.

 

[That'll Buff]

To add onto this, another question. I've never fully dug into a diff, just mildly cleaned it and changed the oil when I got the axles. I have watched a few videos and read a few threads on replacing gears, so I know the general process there but not when it's just the carrier. Intuition tells me it's the same process with measuring gear pattern, shims, backlash, etc, but the small amount I have read about a carrier only swap makes it seem much simpler than that. Mostly just checking backlash on the ring gear. Maybe I'm misreading some of the posts, so let me know what all to expect.

 

[rasband]

I know I am borrowed time with my OEM lockers, hoping to take care of that this coming winter. There's often a debate about E-Lockers vs Air Lockers and after watching how much movement the E-Lockers needed when it mattered, ARB is the way to go.

 

[That'll Buff]

I know I am borrowed time with my OEM lockers, hoping to take care of that this coming winter. There's often a debate about E-Lockers vs Air Lockers and after watching how much movement the E-Lockers needed when it mattered, ARB is the way to go.

That's what's pushing me in the direction of ARBs, even if they are more expensive overall. Hearing that E-lockers have to unlock and relock whenever you reverse and go forward makes me pretty wary of them.

 

[Apparition]

That's what's pushing me in the direction of ARBs, even if they are more expensive overall. Hearing that E-lockers have to unlock and relock whenever you reverse and go forward makes me pretty wary of them.

I have seen e lockers not work for various reasons on multiple occasions. My ARB's, even when the seals were leaking and needed replaced, have always locked.

 

[sab]

That'll Buff, didn't you have an epic end-of-college-need-to-start-real-life-soon Moab trip planned for this month? Did you already do that, or are you scrambling to get ready for that still?

 

[That'll Buff]

That'll Buff, didn't you have an epic end-of-college-need-to-start-real-life-soon Moab trip planned for this month? Did you already do that, or are you scrambling to get ready for that still?

Yup, finished that up yesterday. Had a blast even if it lead to some pretty expensive fixes. First day before everyone was there and we only had a small group, we ran 3D since it was quick and close to camp.

Monday with everyone there we ran Sevenmile rim and wipeout hill, which caused the first of many big issues with the group when one of the Tacoma guys' lockers (theoretically) didn't shut off at the end on the trip back and broke his ring gear.

Tuesday we got ourselves into a good bit of trouble. Ran poison spider to start. Maybe half way through a JK guy broke the plastic bushing that connects to his T-case shifter and it got locked in neutral. Had to manually shift it into 4lo while in the sand. Right before the loop, we had an XJ guy break a stock axle shaft in the rear (35s with spacers on a dana 35 with an lsd breaks shafts, who could've predicted that). Luckily he had spares and was able to get it swapped. By this time it was around 3 or 4pm and we really should've either done the loop or just turned around, but somehow in our infinite wisdom, the guy leading the group decided to do golden spike and we didn't say no. This lead to us doing golden spike, golden crack, and Gemini bridges. No further major breakages that lead to stops thank God, but nobody came out of that unscathed. Other XJ guy got a new rear window installed when a tree pushed in his tailgate from the side (somehow didn't break any glass). Waterfall scared the crap out of us considering we got there at like 2am, but luckily we had enough winches to get everyone up. We didn't get back to camp until around 4 am, meaning we had wheeled for about 18 hours.

Wednesday we took it easy, mostly milled around town. We decided to do backwards bill starting from the wipeout hill trailhead and heading west from there away from wipeout hill.

Thursday we did the first part of Fins and Things while we waited for a couple of people then did Hells Revenge. I wimped out of doing Hells Gate and just watched my most of my friends and a group of dirt bike riders climb it. Met some Yokohama sales reps and dealers doing a jeep tour while there too and got to show off our group, but nothing much came out of it. Finished up Hells Revenge, passing on the other named challenges on the trail. I was already planning to load up and leave that night, but the locker issue only made it more necessary.

Had a ton of fun and can't wait to do it again, but not before some serious repairs and improvements.

 

[sab]

Yup, finished that up yesterday. Had a blast even if it lead to some pretty expensive fixes. First day before everyone was there and we only had a small group, we ran 3D since it was quick and close to camp.

Monday with everyone there we ran Sevenmile rim and wipeout hill, which caused the first of many big issues with the group when one of the Tacoma guys' lockers (theoretically) didn't shut off at the end on the trip back and broke his ring gear.

Tuesday we got ourselves into a good bit of trouble. Ran poison spider to start. Maybe half way through a JK guy broke the plastic bushing that connects to his T-case shifter and it got locked in neutral. Had to manually shift it into 4lo while in the sand. Right before the loop, we had an XJ guy break a stock axle shaft in the rear (35s with spacers on a dana 35 with an lsd breaks shafts, who could've predicted that). Luckily he had spares and was able to get it swapped. By this time it was around 3 or 4pm and we really should've either done the loop or just turned around, but somehow in our infinite wisdom, the guy leading the group decided to do golden spike and we didn't say no. This lead to us doing golden spike, golden crack, and Gemini bridges. No further major breakages that lead to stops thank God, but nobody came out of that unscathed. Other XJ guy got a new rear window installed when a tree pushed in his tailgate from the side (somehow didn't break any glass). Waterfall scared the crap out of us considering we got there at like 2am, but luckily we had enough winches to get everyone up. We didn't get back to camp until around 4 am, meaning we had wheeled for about 18 hours.

Wednesday we took it easy, mostly milled around town. We decided to do backwards bill starting from the wipeout hill trailhead and heading west from there away from wipeout hill.

Thursday we did the first part of Fins and Things while we waited for a couple of people then did Hells Revenge. I wimped out of doing Hells Gate and just watched my most of my friends and a group of dirt bike riders climb it. Met some Yokohama sales reps and dealers doing a jeep tour while there too and got to show off our group, but nothing much came out of it. Finished up Hells Revenge, passing on the other named challenges on the trail. I was already planning to load up and leave that night, but the locker issue only made it more necessary.

Had a ton of fun and can't wait to do it again, but not before some serious repairs and improvements.

View attachment 688743

That's the kind of trip that when you're old and gray (like me), you'll look back at fondly. Epic! I'm glad you've got that done. I was worried this locker issue was going to prevent you from going...