Rubicon Locker Problem

[Bud125]

Went wheeling with the Jeep club yesterday and we climbed a local mountain had a blast but when I got to the top I started to hear some noise from the rear dif. It was not constant or anything and my locked light stayed on. Didn't have much choice but to just go back down, this is a pretty tough trail. Got to the bottom and tried to unlock it and the light just flashed constantly. Drove for a way on a dirt road and the light finally went out. Started down the black top and started getting the noises again, popping etc. especially when turning. So we stopped, my son went and got his trailer, and we brought the Jeep home. I was expecting carnage inside the rear dif but no broken teeth or metal or sparkles in the fluid. But it is definitely still locked. If I try and lock it with the switch it just flashes, the pump does come on and shuts off after it pressures up, there are no leaks anywhere that I can find.
The actuator ring does not seem even , left to right compared to the rest of the locker.
Any insight on this would be appreciated.

 

[Jerry Bransford]

Did you ever engage the locker while the wheels were spinning? Doing that can tear them up. I suspect its limited slip differential that is part of the rear locker has come apart.

 

[Bud125]

Did you ever engage the locker while the wheels were spinning? Doing that can tear them up. I suspect its limited slip differential that is part of the rear locker has come apart.

Negative, I always engage the rear locker as soon as I am on dirt or start on the trail to avoid that from happening. Is there a way to tell if the limited slip is causing the problem?

 

[Jerry Bransford]

Negative, I always engage the rear locker as soon as I am on dirt or start on the trail to avoid that from happening. Is there a way to tell if the limited slip is causing the problem?

Good to read you know the drill on when and when not to engage it. I can't say how to tell if it's the LSD that has blown, it has not happened to mine. I suspect @mrblaine knows what the symptoms of a blown LSD inside the Rubicon locker are.

 

[mrblaine]

Good to read you know the drill on when and when not to engage it. I can't say how to tell if it's the LSD that has blown, it has not happened to mine. I suspect @mrblaine knows what the symptoms of a blown LSD inside the Rubicon locker are.

In his case the big clue is the ring and flange is canted. That can be caused by bits of gear teeth lodged in the actuator and clutch ring, a blown actuator collar, or some other bits out of whack like the companion ring having its tabs sheared off. Hard to tell without some disassembly.

 

[Bud125]

In his case the big clue is the ring and flange is canted. That can be caused by bits of gear teeth lodged in the actuator and clutch ring, a blown actuator collar, or some other bits out of whack like the companion ring having its tabs sheared off. Hard to tell without some disassembly.

Thanks for the info, yes disassembly is next.

 

[jjvw]

One prominent sign that the LSD is breaking apart and clogging the works is if you notice catching and hesitation while turning. Eventually the hesitation turns into a crunchy sound and feeling. Then the rear will lock up hard during turns followed by loud cracks as the diff opens up again for a while.

Disassembly is almost pointless because there is no fixing it.

 

[Bud125]

One prominent sign that the LSD is breaking apart and clogging the works is if you notice catching and hesitation while turning. Eventually the hesitation turns into a crunchy sound and feeling. Then the rear will lock up hard during turns followed by loud cracks as the diff opens up again for a while.

Disassembly is almost pointless because there is no fixing it.

Yes, that's what is happening to me. Looking at replacement lockers, lots of decisions to make and I need to get back on the trails asap!! Our season is so short!

 

[jjvw]

Yes, that's what is happening to me. Looking at replacement lockers, lots of decisions to make and I need to get back on the trails asap!! Our season is so short!

I like my ARB that replaced the factory locker/LSD.

 

[Bud125]

I like my ARB that replaced the factory locker/LSD.

So if I replace my factory locker with an ARB or an Eaton would I have to replace the ring & piñon as well or could I reuse my stock 4.10 set?

 

[jjvw]

So if I replace my factory locker with an ARB or an Eaton would I have to replace the ring & piñon as well or could I reuse my stock 4.10 set?

To use your stock thick cut gears, you need the ARB117, which is the 3.73 and numerically lower carrier that is used with standard cut gears. The equivalent would be used for Eaton. The existing ring gear transfers over. You will need to run a gear pattern and understand how to measure and keep the backlash between the old and new carrier.

 

[Bud125]

To use your stock thick cut gears, you need the ARB117, which is the 3.73 and numerically lower carrier that is used with standard cut gears. The equivalent would be used for Eaton. The existing ring gear transfers over. You will need to run a gear pattern and understand how to measure and keep the backlash between the old and new carrier.

Great information, thanks.

 

[mrblaine]

Yes, that's what is happening to me. Looking at replacement lockers, lots of decisions to make and I need to get back on the trails asap!! Our season is so short!

Fastest would be just to get another OEM locker and toss it in. The problem with that is they are all used, no one selling or buying one knows how far any of them are away from doing the same thing as the one that its replacing. It could last a very long time or crunch the limited slip gears next trip out. The biggest mistake owners make it not locking it up as soon as they get on trail. That works the limited slip too hard and tears up the gears. I have a few for my own personal use and I refuse to sell them because I don't trust them to last.

 

[Jerry Bransford]

So if I replace my factory locker with an ARB or an Eaton would I have to replace the ring & piñon as well or could I reuse my stock 4.10 set?

You can reuse your gears if you set the backlash properly. Measure it before removing the Rubicon locker then shim the replacement so the backlash is exactly what it was before.

 

[Bud125]

Fastest would be just to get another OEM locker and toss it in. The problem with that is they are all used, no one selling or buying one knows how far any of them are away from doing the same thing as the one that its replacing. It could last a very long time or crunch the limited slip gears next trip out. The biggest mistake owners make it not locking it up as soon as they get on trail. That works the limited slip too hard and tears up the gears. I have a few for my own personal use and I refuse to sell them because I don't trust them to last.

Yes, I always followed that rule on locker engagement but who knows what the PO did. Think I am pretty much done with stock locker set up. Not much of a local supply anyway.

 

[Bud125]

You can reuse your gears if you set the backlash properly. Measure it before removing the Rubicon locker then shim the replacement so the backlash is exactly what it was before.

View attachment 426889

This is the route I am planning on now, East Coast gear has what I need in stock. Going to give it a shot anyway.

 

[Accelerometer]

The biggest mistake owners make it not locking it up as soon as they get on trail. That works the limited slip too hard and tears up the gears. I have a few for my own personal use and I refuse to sell them because I don't trust them to last.

Sorry new guy here and I come from the world of Toyotas. I'm curious to understand why it's a good idea to by default lock the rear up whenever you're on dirt. This is the first time I've had a vehicle with a combo LSD/Locker in the rear, i've mostly run completely open diffs with a selectable locker. Best practice with those is to lock up when you know you're approaching a tricky piece of trail and then unlock once your past that bit. Locking the rear full time introduces less than ideal handling dynamics when cruising more mellow parts of a trail.

To the OP, I'm a huge fan of Eaton E-lockers. A few years ago I self installed one in my 5th Gen 4runner and it has worked flawlessly ever since. As mentioned above all you need is some research, an accurate dial indicator, gear pattern marking paint and a whole lot of patience. It's a pretty straight forward install that many including "professionals" mess up but it isn't hard. You just need to sweat the details and be meticulous about getting things dialed in properly.

 

[mrblaine]

Sorry new guy here and I come from the world of Toyotas. I'm curious to understand why it's a good idea to by default lock the rear up whenever you're on dirt. This is the first time I've had a vehicle with a combo LSD/Locker in the rear, i've mostly run completely open diffs with a selectable locker. Best practice with those is to lock up when you know you're approaching a tricky piece of trail and then unlock once your past that bit. Locking the rear full time introduces less than ideal handling dynamics when cruising more mellow parts of a trail.

The OEM Rubi rear air locker is also a gear driven limited slip. The gears tend to break the teeth off and the small pieces get circulated through the diff which causes all manner of issues. It also happens on the street when you corner aggressively.