How does Jeep vacuum disconnect work???

Dana 30 front axle. What actually engages and disengages this axle? I took the vacuum actuator off, and there is a shift fork that rides on some type of devise that slides back and forth on the axleshaft. I am planning on putting this axle under an S-10, and need to know how to make it function correctly. I heard that it would cost big money to convert to manual hubs. Any information and how this system works would be appreciated.

"Joe Peters" wrote

Follow your vacuum lines from the front axle back. I think that you will find that it is controlled by a switch in the t/case that simply applies vacuum to the actuator when you select 4 wheel drive. The GM system works in a similar fashion, just that the parts look different.

If all you have is the axle, then you will have to figure out how to supply vacuum to the actuator when you select
4 wheel drive. If your s-10 is a 4x4, you can simply use the vacuum line that goes to 'its' vacuum actuator.
Under the battery tray is where it resides.

if you go to www.quadratec.com you can look up a cable conversion for this axle. the vacuum system is ok, but sometimes can be unreliable for off-roaders. the cable system bolts in place of the vacuum actuator and the handle goes in the cab and you can lock/unlock the axle whenever you please.

note this is NOT a locking differential, just an axle disconnect

One axle is connected to the diff all the time. That collar inside on the fork slides across and locks in the other axle so the diff becomes engaged.

There are two main vacuum lines to the actuator. Put vacuum to one and the shift fork slides to 'lock' the axle, put vacuum to the other nipple and the fork slides to 'open' the axle.

I 'think' some have a third nipple which is used to fire up a relay for the 4x4 light.
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's