Ive been getting diff fluid coming from the front axle vent tube. So after some investigating ive found that the actuator is not dissengaging the hubs when placed back in 2WH. When I manually push lever to the 2WH position the front drive shaft spins freely but as soon as I start the truck it moves back to the 4W position. Is front actuator bad or maybe vac lines.

 

i just went through mine and sounds like it has vacum line problems or solenoids. you should have two solenoid sensors on your firewall right behind you battery that the vacum lines from your front diferential go up two .alot of times the vacum lines get britel and crack usualy up around your battery . also you might wana check and see if you vacum reseve tank is not cracked and holds vacum . to check your reserve you will need to pull your battery out, it is right in the back of batery box , you should see vacum lines from the solinods on firewall going to the reserve tank