The CAD is engaged or disengaged as I set it. No problems at all with the CAD doing anything but what I set it at. I bet you could pickup a vacuum accumulator ball at the junkyard for next to nothing. They literally last forever.

This is the easy way but it isn't cheap.
http://www.4x4posi-lok.com/app_dodge.html

 

Yeah, vacuum can its not exactly a wear component. No reason for one to fail. I would love to ditch the vacuum and run that posi-lok setup from the link you posted. I just cant justify that kind of money for that. I have thought about building my own using a locking throttle cable similar to one like this - http://www.zorotools.com/g/00108370/..._Shopping_Feed
A cable like that and a little creativity would make a pretty sweet posi-lok IMO.

 

The price is why I did it the way I did. I looked at using that type cable to make my own cable lock. The problem is the location of where the cable comes out of the actuator and the location of the leaf spring. There isn't much room there to make a turn and the solid cable doesn't do corners very well. You are also up to $50.00 before you even start.