I have no vaccume at the hoses ( wheels ), where is the next place to look for a leak or something broke??? The transfer case works & putting the hubs in manual got me out of the ditch.
could be the oring inside the hub...first trace all the lines from the hub to the pump just to make sure one didnt crack or break...next check the lines from the pump to the fire wall for the derost...
If you have no vacuum at the hose end, trace the hose back to the solenoid that switches the 4 wheel drive. It is an electrical/vacuum device. Is your heater working properly? If not you need a new vacuum pump. $100 at my local junk yard (now called recyclier).