Okay so I took it apart again. I took out that Allen Bolt and rotated the gear assembly around until I could see the notch that it goes into through the hole. I put the bolt back in the proper position and now the gear has very noticeable spring tension as it engages the clutch. Apparently the previous owner must have had the oil change and thought that was the fill plug. Hopefully this resolves my lack of rear Locker and transmission fault codes. Thanks for the quick replies, you have been more help than you know

 

Cool. Keep us updated on how it all works out!

 

So it's back together now. When I turn on the key I now get a transmission fault stop with care message instead of the traction reduced message. And it says special programs unavailable. I'm assuming because everything moved around so much it needs to be recalibrated with The Gap tool?

 

Maybe. The rear diff should self-calibrate for the most part. The function is also in the GAP tool for a self-test, which is also a calibration. Codes specific to the rear diff may give an actual idea to the issue. You never did answer if you can move that half-gear 360? I am not sure how much it would really move anyway but like I said, one would think the "default" state with that pin back in place would be backed off the clutches or "unscrewed" along the axis of the diff. So if you backed it off all the way and then installed the actuator I think mechanically, at least, you are correct.

So next I would make sure you have the actor harness 100% plugged in, not an easy thing to get right honestly. Then I would try a hard reset of the truck - disconnect battery for a while. After all that I would simply try lots of cycling of the key to on position. When you do this, without actually starting, you can very much hear the hum and some soft clicks of the rear diff actuator. So do that a lot to help it maybe calibrate a bit. And if all else fails, just wait for the GAP tool to arrive. Then you can get the exact codes you have for the rear diff and really see what is going on. I think my only fear would maybe the clutches got destroyed and it can not actually calibrate somehow.

Did you replace the actuator with a new one? Was it OEM?

 

With that bolt installed it would not rotate a full 360, only until that part with the groove in it would make contact with that stopper bolt. My assumption is with the bolt out it would rotate it full 360. From what I can tell that bolt has to be in place on that item number five in the exploded diagram, otherwise the whole assembly just rotates. With it locked in place however the gear has notable spring tension that defaults one position which I'm assuming is open. I did not replace the actuator yet, I wanted to take this one apart and see if there is any obvious problem with it. I can hear it operating when I cycle the key so I'll try to keep doing that and see if it calibrates

 

Right. But with no bolt, I wonder how far it should be spun back or in? My thought, and again making assumptions. Is that the half gear can actually be spun more than just the short distance it can with the stopper bolt installed. The gear works by varying pressure on the clutches. So my random baseless thought it that at the factory, that gear it basically "set" so there is just the right pressure on the clutch packs, or none, then the stopper bolt thing is installed to lock that range in. Or think of this scenario. If the clutches are worn, could someone remove the stopper and spin the gear one turn to increase pressure on the clutch pack when actuated? Again, just a theory. So with that said, I am just wondering if that is how the gear works, if it should be turned in or out to a certain tolerance before the stopper is installed. I am not overall confident in that assumption based on how little it actually operates anyway (the range, being only a half gear).

When I operate mine with the key, I think there is a hum with a small break in the noise. Like two short hums back to back. With a faint lick at the start or end or maybe both ends. Also keep in mind the center diff also does some stuff with key turn also, so maybe the clicking I am thinking of is the center diff and only the hum-hum is rear diff.

 

From what I can tell, it looked like the whole assembly, clutch pack and all rotates together with that bolt out. So I don't think there is any baseline setting that is being changed if that moves.
When I hat the actuator out and apart I moved the gears a lot, so I'm guessing there is a position sensor in there that is no longer where it used to be.

Problem now is that I'm stuck with lowered suspension and can't drive anywhere. Before I "fixed" it it was perfectly drivable. Hope the gap tool is able to fix it. I have a new actuator ordered as well. Getting the $150 one on Amazon.

 

Pretty sure the only sensors are in the actuator itself. You may be able to simply pull the fuse for the rear diff module. Then that way it can not directly report a fault and I think you then regain most of your systems. But you may need to hard reset again to clear any lingering codes. If I recall, I drove that way for a short time until I did my actuator. (or maybe I edited the truck config file to remove the locking ability, I forget!)

 

I still get the fault with the fuse out. However I have the xlifter suspension controller so putting that in the off road mode put me back to a standard ride height.
At this point I'll leave the fuse out till the gap tool arrives so it doesn't keep cycling the actuator.
Again thanks for your help. There isn't much info on these diffs so the more we can figure out the better. Hope it helps other people keep these things alive.

 

Ok I got the gap tool. Attempted to run the rear diff test and it says failed test e 7. Code is clutch position sensor circuit range performance.