Im in the midst of a tranny/trans case rebuild and was thinking about the little vacuum switch that engages the CAD. I just replaced the actuator a little while ago, but was wondering about a switch on the dashboard that could stop the vacuum pull in 4Low, giving me the option of 2Low? Ive looked and found nothing on the Web....

 

you would actually need to switch the vac flow.

vac on one side moves the shift fork to engages the collar (4wd).
vac on other side moves the shift fork to disengage (2 wd).

no vac = no movement. it stays whereever its at, unless it decides to move on its own.

i'd recommend a posilok. alloy is making them now for cheaper. about $125 or so.

 

I know, but I just replaced mine last year and I'm too cheap to pull it out for no reason.... I liked the idea of it working normally until the rare moment I need 2Low

 

Older Cherokees (70's and early 80's quadratrak) had a vacuum switch in the glove box.... not sure if it would serve your purposes, but, might be worth checking into.

 

i can't quite figure out an easy and inexpensive way to maintain normal switching operation in normal mode and then an easy "reversal" of the vac lines at the cad. especially without bringing the vac lines into the cab where you could operate some type of manual valve. sounds like something to stay broken all the time.

i think that without vac on the proper side, the stupid collar will always be trying to float to where ever you DON'T want it and you'll get grinding or pop-off.