RR Diff Locker Stuck?

Howdy TW. I've been working on my '98 4runner with the factory rear e-locker. I recently swapped the 3rd member (4.30 gearing) out, as the previous rear diff had been run dry by the previous owner (due to leaky rear axle seals, fixed those and did rear wheel bearings too). I scored a used rear diff on eBay for $450 and threw it in. Once I got the rig put back together it was clear the rear diff was locked up as it's dragging the outside rear tire whenever I turn more than like 3 degrees.

I've removed the actuator and checked that it does extend when the diff locker button is pressed, and retracts when it's pressed again. Nonetheless I can't get the diff to unlock after I reinstall the actuator. I can only seem to install it with it in the "engaged position". Any advice on how to proceed would be helpful. It may be worth noting that I can't get 4wd to engage, but I can tell the transfer case does engage and the front driveshaft spins, it just seems the front differential's 4wd actuator isn't engaging (that was next on my list after fixing the rear diff). Any chance that would affect the rear locker not disengaging? Hoping to not have to pull the 3rd member once more to get it unlocked.

 

Have you try to manually move the slide gear in the third member to unlock? You can do that by removing the actuator.

 

No I'll have to try that. Is that the circular gear that you can see the bottom portion of inside the top part of the hole the actuator feeds into?

If so will it be easier to move it with the rear end up in the air and the truck in neutral? Can you usually move it by hand? Or use something like a screwdriver?

 

You can move it easily by hand. That's what I'd done before, if not, a flat head will do. Once you pull the actuator out, shine a light in there, you'll see some gear teeth, side or to the right (unlock)

 

Awesome will do. Thank you sir

 

Just a quick update: I pulled the actuator again today and the slide gear felt very stuck. After trying a few things, I got it to release only once I jacked the rear end up and out the truck in neutral. Then I wiggled the wheels back and forth while using a screwdriver to pry gently on the slide gear. Thanks @02hilux for the pointers

 

One more question though. While fiddle farting under the truck I've noticed a small leak coming from the seam between the diff and the carrier. I used Permatex Ultra Grey to seal it and felt I did a good job of not preemptively smearing it before getting the diff installed.

I drained the diff tonight and plan to try and smear a little more Permatex over the area in the seam that appears to be leaking tomorrow. Then I'll let that dry dor a couple days before filling the diff back up and driving the rig. Any alternative thoughts on how to deal up this leak without pulling the diff again?

 

Not much. Did you let it settle/cured for at least 24hrs?

If the gear oil is seeping out, there's not much you can do. Even if you drain and try to force silicone in, the oil is already present and won't do any good.

 

Yea I let it cure for a few days actually because I got sick in the middle of this project. I kinda figured I was screwed when I saw the drip today, but was hopeful someone might have a novel solution that would save me the headache of pulling the diff again.

I wonder if test driving it with the diff locker stuck yesterday actually torqued the diff away from the carrier just enough to open that little seam up.

 

Strange... as much a you hate redoing it, you'll have to take it apart again, clean it very well, and reseal.

 

Been there too! The locker can be very finnicky if installed incorrectly. Be sure to make sure it fully engages when on also. I had a situation to where I got mine unlocked, but the locked position was barely locking the diff. When I got into some slick situations that warranted a locker, it made the craziest noises as the locker was slipping (due to partial engagement).

 

Good to know. I'll test it out once I get the leak in the diff carrier fixed. I was just aiming to get the diff unlocked for now, as I have an appointment to get the truck aligned Tuesday and didn't want to drag my locked rear end all the way to the allignment shop.

 

I'm thinking I'm gonna try draining it, smearing a little more sealant in that groove today (letting that cure for a couple days), then refilling it (at least to go get it aligned next Tuesday). If that doesn't work (which it probably won't) then after the allignment I'll pull the diff back out and fix the leak properly. At least on the bright side I'm doing a drain and fill since the last diff left metal shavings all over the carrier from being run dry by the PO. I cleaned it out best I could, but I'm sure the gear oil will pull a bit more metal shavings out that i missed.

 

I did the same thing resealed it and it leaked. Make sure the breather is working. Then take a wire wheel and clean the edge of the mating surfaces. I'd drain the diff so it's not leaking into the sealant as it dries. I smeared some on the side and it hasn't leaked since.

 

Nice, that's what I did last night. I'll fill it up tomorrow and we'll see if I can be as lucky.

 

So I got lucky, or at least it appears so this far.

Fluid's been in there since midday yesterday and no leaks. Haven't yet driven it (will tomorrow to the alignment shop), so if that doesn't cause it to leak, I should be in the clear.