• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Disco axle not engaging

boise49ers

NAXJA Forum User
Location
Boise,Idaho
I got gears last month and now my dis-connect isn't working. How do you shim the collar so it is always engaged ? Any write ups on this would be cool.
I'll trade a whole Dana 35 rear axle for a passenger side Dana 30 axle shaft. That would work in a 1988 dana 30.
It would have to be close to Boise though. Sure don't want to ship a whole Axle. I don't expect any takers, I know those 35's aren't exactly hot items.
Help would be nice though.
Thanks !
 
Did you check the vacuum lines? The lines between the body and axle tend to go bad or just pop off. I have used the cable activated Posi-Lok for a few years, it works but is not real convenient, and is pricey. Looking at my old vacuum activator, I'm not sure if it comes apart so that you can just fit some washers on the fork shaft to shim it. I'd probably just drill a hole on the side opposite the vacuum can, and run a bolt into the fork to lock it where I wanted it.

If you replace the two piece shaft with a one piece, you'll need to add a seal on the passenger side diff housing.

Fred
 
Yeah I have research a little more and found the seal thing out. Bummer !
I really don't feel like tearing that far into it. Locker install was enough. I'll tear it apart and see if i can't figure out
what your idea would take. The washer idea doesn't sound to bad. You have to use like 10 or 11 though.
Thanks !
 
The Dana 30 washer fix is easy to do. I've did it on my YJ when the back of the fork broke off.

There is a write up, but i can't be bothered to google it right now (it might be on Junior Users).

OK, pull the vacumm motor (the assembly on the back of the axle), leave the hoses and wires connected. Before doing anything else, start the engine (trans in neutral!), and engage 4wd (Hi or Lo, doesn't matter), see if the fork slides back and forward. If it doesn't, you've got no vacumm. Up to you to troubleshoot that problem!

As far as the washer fix, NOW pull off the wires and hoses. Go to the bench and pull the 3 clips on the fork shaft (2 small, 1 large). Just inboard of the diaphram housing (The big round bit), is a place to unscrew and remove the shaft. Now you need to find about 10 washers that fit over the shaft, but also fit inside the housing. Can't remember what size i got for mine. Take the whole thing to Home Depot hardware aisle if needed.

Now you've got the washers, hold the housing V pointing to the floor. Start to slide the shaft back in. As you slide it in add washers until you have the shaft almost all the way back, but just enough room to fit the fork back in. It should take about 10 or 11 washers IIRC. When the fork is held snugly on the shaft by the washers, tighten the shaft back up.

Slide the big ring that joins the axle shafts in the axle together to the middle of the axle, ie towards the diff. Now replace the whole assembly, making sure the selector fork goes around the ring. Bolt it all back up, re-attach everything (even if the hoses didn't work, at least you don't have to figure out what to do with them!) and you're done.

You didn't say if you have a front locker. If you do, you'll be staying in 2wd whilst on tarmac, or getting a big surprise!
 
Not real convenient, but my brother has an 87 YJ with the disco axle, he pulled the whole assembly off and used a hose clamp to lock in place for the weekend. Then he pulled it out to remove it after. Worked, kinda jerry-rigged? FWIW
 
Ended up a broken fork. I did the washer thing , but it didn't line up unless I turned the actuator assembly upside down. Then the collar lined up. I'm just gonna leave it like that until I get a assembly from a friend who has one. Works fine like it is right now though. I'm just worry the rest of the fork will snap at some point.
 
The fork out of a Dodge ram is steel, much stronger, and will work. I just went to a Mopar dealer and asked for a shift fork out of a Dodge Ram. It's around $70.

Fred
 
The guy I know doesn't have his anymore. I'll hit the boneyards. They sell the whole assembly for $25. I may still shim it. I just don't want a broken fork inside the housing that may go at anytime.
 
boise49ers said:
The guy I know doesn't have his anymore. I'll hit the boneyards. They sell the whole assembly for $25. I may still shim it. I just don't want a broken fork inside the housing that may go at anytime.

Who did the gear work? probably didnt hook up the vaccum lines. I would not wrry about he fork breaking, a second ring in there is enought to lick em together full time
 
The vacuum was working. It was the fork being broke that did it. Unless them being hooked up wrong can break the fork. I only have the original fork in there. 2/3 of it is still there. The bottom 3rd broke off. I have it shimmed with washers on the plunger rod.
 
I ended up just replacing the vacuum disco I didn't care for the poppin when I did tight turns from the locker. This way I get no poppin. I need to replace the rubber station that the three llines hook into though. They fit very loose and I'm sure are loosing vacuum. :wave:
 
Back
Top