The lockers in my 08 haven't always worked well (until more recently). I read the manual and searched the net for suggestions when my new rubi lockers enguaged intermitently. I tried to enguage at sloooooooooow speeds and a bit faster, I turned left and right, forward and backward, then decided to take it in for service (under warranty). The dealer replaced a sensor and sent me on my way. A couple days later, the problem returned (I don't think it was ever fixed). My dealer likes to throw parts at problems and send you on your way.
I took it back in and they replaced the rear differential. The problem got better, but the locker (both front and rear) would not lock up on demand. This is important, especially on the front when you don't want to drive with it on all day.
On one offroad trip, my rear locker refused to dissenguage. It took more than a day of fiddling with it to get it to release. Now for the good news...
After changing the fluid in the front and rear with Mobil 1 75-140, the lockers began to behave! From time to time I still get the flashing light (mostly in the rear), but it dosn't last for long. When used often, it works much better than when it has not been used.
Here's what I think... new synthetic fluid helps, but use makes all the difference! The more you use them, the better they act. At this point, mine function just the way I want 99% of the time with nearly no delay. Swap out that fluid and do all you can to manualy enguage the locker with a friend in the cab toggling the switch on and off.
To answer your question, no, you don't need to enguage one locker before the other.
Good luck,
Nathan

 

As mentioned earlier with the lights flashing , Mine has done the same thing as well since new . the manual does nothing to help or explain anything about it other than engaging and disengaging at a certain speed if i can recall correctly .
I have thought this was just normal and have contemplating bringing it in for servicing . but the Option of changing fluid and using it more sounds sensible as well . I have less than 5k on the odometer and have used the lockers less than 20 times

 

hello fellas.. i just bougth a 2010 jk rubicon and try to lock both axel.. they both work fine but when a press the bottom to turn it off jus the front axel trun off.. my rear axel kept flashing the light in my dash and and does not unlock .. any idea what is wrong with it ??

 

It sounds like a sticky locker. Most people have issues with the actuator dying and not being able to get the unit locked. If you get it locked and can't get it unlocked, it is likely the interanl wave spring which pushes the dog clutch away when the magnet is deactivated. The bad news for you here is that if that is indeed it, there's no solution outside of replacement.

I don't have pictures available at the moment, and damn photobucket's policy made most of Ronjenx's pictures in this thread worthless -
https://www.jk-forum.com/forums/stoc...-study-263666/

Google some pictures of the rubi locker. You should be able to open the fill hole in the diff cover and be able to get a screwdriver in there to pry the actuator ring from the left to the right to disengage the locker. Worst case scenario you may need to remove the diff cover.

My locker gradually got worse over time. it used to just be sticky, then got to the point that once locked, i'd have to manually pry the ring every time. It sux mainly cuz there's no great replacement. either another rubi locker which costs too much for what it is, or a new 35 spline unit which then requires new axle shafts and a regear job.

 

Im revisiting this thread to explain what Im currently doing.
1) rear axle locks, front did not (light just flashed). Was able to check that the relays were clicking. A good starting point is to read up on the locking diff override and how the relays send 12Vs to the actuators.

2) With the front diff cover off I could see the actuator moving over but not far enough. I did this test using the Jscan app which allows me to lock the diff with my smart phone and the OBDII port. I was able to make it lock by pushing it over more with a screwdriver but it wouldnt stay that way.

3) I removed the center section/carrier (pulled axles and removed the bearing caps - used a rag pulled into the pinion and some pry bars to pull it out). On the floor I could actuate the magnetic coil with a 12V power supply. It pulls about 3 to 4 amps but it behaved the same as when in the axle housing. Doesn't plunge far enough to lock the axle.

4) it appears to be a common problem that the plunger inside the actuator wears away which results in this failure, the plunger still actuates but not enough to push the locking dogs into place. I have ordered a new actuator - these retail anywhere from about $150 to $300! I also got a new bearing for that side because to get the actuator off you have to take the bearing off. I used a grinder to grind a grove in the inner bearing race and then a chisel to crack it and remove it. its probably more correct to use a bearing splitter and hydraulic press.

5) reinstallation is a little tricky because you need to use a small piece of dowel to hold the Sensor at full extension while you put the center section back in with a small thread of string attached to the dowel. Once the carrier is in place you yank the spacer/dowel out to allow the sensor plunger to move again. The sensor is totally independent from the actuator and just senses the movement of the locking plate - when it doesnt go far enough the system senses this and thats why the light flashes in the dash. Theres a thread in wrangler forum where some others have completed this same process and got theirs working again. It seems the actuators wear out anywhere from 75k to 150k miles (mine has 129k but it could have been malfunctioning a while because it was bad when i bought it at 127k)

Im surprised there isnt like a megathread on this information anywhere online nor any good youtube videos.