4wd ?

If the Dana 30 vacuum actuator doesnt work will at least one front tire spin? No tires spin in front when in 4wd and seems like my transfer case is engaged. A mechanic told me if the vacumm actuator fails at least one tire should spin in the front.

Only if you have a locker. If not it will spin the inner shaft cause it has no load.

no locker just stock

Then you only have 2wd

See my post in this thread for full test procedure on the D30 CAD axle vacuum system:

http://www.naxja.org/forum/showthread.php?t=980642

JP Magazine's take on the D30 CAD and other options:

http://www.jpmagazine.com/techartic...154_0904_dana_30_vacume_disconnect/index.html

Until I purchased the actual Posi-Lok I did a variation of the drill/bolt/nut on the collar's fork--I took a shock bolt sleeve and cut it off to the correct length to hold the shift fork in the engaged position full time. Some have posted up they did the same thing using a stack of washers.