Rear Axle rebuild if locker won’t engage (1 Viewer)

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smittycrusher

"Hey big guy, you a golfer" - Roger Dorn
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Everything I read says that you are to lock the rear on the factory locked trucks if you are going to rebuild the axle.

Is this a best practice or a must do?

My rear won’t engage and I pulled the actuator off last night and disassembled. It actually looked great inside so I just cleaned the old grease, added new grease and put it back together. Still doesn’t work. I will pull it again and connect to the front actuator since it works very quickly. If it works, then I start figuring out electrical or ECU issues.

All that to say, do I have to wait until I get this sorted before I can rebuild the axle and install the RCV 300m that I just got from @cruiseroutfit ?
 
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To pull the third the diff has to be locked the fork and gear make contact with the housing if you don’t. With the actuator off you might be able manually Engage.
 
If you can get the actuator off, you should be able to pry the clutch over to engage, that way you can pull it out of the housing.

Are you planning to pull the diff or just swap shafts and rebuild the spindles/bearings?
 
So if I don’t plan on removing the third member, I don’t have to have it locked?

I plan to follow this write-up:
 
After I rebuilt my actuator I plugged it in and tested it before I reinstall it to make sure it was working
 
I R&R's the hubs once when the locker was inop. Didn't present any issues for me, but I was warned the collar can be forced off of the shift fork if the locker is not locked. YMMV...
 
So if I don’t plan on removing the third member, I don’t have to have it locked?

I plan to follow this write-up:

No, you'll still want it locked, particularly if you're just sliding a shaft in an out. I was just curious how far you are going. It's easier to repair and test the locker actuator with the diff on a bench BUT it's not worth pulling the diff if you dont have to.
 
Thank you guys for all of your help. I will work on tracing the issue to the actuator, wiring or ecu. I am glad that I asked before I started pulling shafts.
 
Visually this is why you should lock the actuator on the rear axle (manually or electrically) prior to pulling the short shaft.

B30E6AA1-733E-45CA-9E47-D8C9712FBBA2.jpeg


6C9AF1B2-30C7-42E1-95A4-BB011B0F6FA6.jpeg


F3228B94-6278-42ED-A91D-3D13007D3FF7.jpeg
 
What do you mean when you say that the rear wont lock? Are you judging this by the lights on the dash? or have you verified by other means (jacking up the rear and spinning the tires) that it's not working?
 
I just pulled the actuator and plugged it into the front, it works just fine. Verified the rear harness isn’t getting power with my multimeter. I guess I get to chase electrical gremlins now. I guess I should start with ECU???

btw...I was blow away with how clean and good the actuator looked when I tore it apart. I would definitely recommend making sure it is getting power before tearing the actuator apart. Rookie mistake on my end.

Here are photos of my internals. This truck has about 280k miles with over 20k off road. I have used this rear locker a good bit. I am very happy with how good it looks inside.

FEF182B9-D9E7-4701-BF09-FC666BC2EFFB.jpeg


223B27D0-9849-497E-88EE-E042AE600A6B.jpeg


6DB9E84D-8F2C-4F92-B3D2-9DCE90422806.jpeg
 
That could go either way, here what mine looked like my reg is 270k
FAC91649-782E-41E2-849C-CEFA75B95ECE.jpeg
E837BC34-ED98-4B06-9A37-D621823A9273.jpeg
 
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How did the o ring look like mine was shot and letting water in. I ran loon creek at Cruise Moab 2019 and after 50 plus creek crossing I started to have trouble getting it to lock.
 
I assume the 99’ 100 series locker actuator is the exact same, right? I could always swap over from my 99’ just to verify the actuator is not the problem I guess. I really dread trying to find an electrical gremlin even though I am pretty confident that is what it is since the rear actuator worked just fine when I plugged it into the front.
 

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