i troubleshooted the whole thing. has vaccuum, cable works, transfercase works etc. basically when you remove the cable from the front axle the rod in the axle wont engage. even pulling it with a pair of vise grips it only moves like a 1/8th of a inch both ways. so basically no 4x4. just curious if anyone has had this happen before.

 

same here took my battery tray off last night and applied vacuum and it pulled the cable but no engagement. disconnected cable and pulled not as much travel as iv heard it was supposed to move and still no engagement . to night i will pull off the cable cover to the diff and look for problems and check spring pin. what could be jamming in there or be giving me this problem .

 

Are you positive you have no vacuum leaks? Because I am going to say you have some, there can still be a little suction on the hose going to the 4wd actuator and still have a vacuum leak. Fallow your vacuum lines from the back of the intake to the tranny as well as everywhere else and also check to make sure your lines arent old and cracking. Also there is a vacuum line running to the window washer fluid resivor that can cause problems. Yes something could be wrong with your front axel but i think it is unllikely after all the problems I have had with my vacuum lines causing similar problems. Your cable could be corroded and rusted up, they are around $25 so maybe replacing it might fix your problem.

 

yes that was a problem also.... heres the full story. it did have vacuum going to the acutator but only 4psi which wasnt enough to pull the axle BUT bypassing all that and even pulling on the cable with vise grips wouldnt engage the axle. so pulled the axle in half and there was a big washer that was broken and bent by that shift fork in there im guessing that had something to do with it. so after replacing the front axle it would engage manually but not with vacuum, it was trying. you could hear it click while spinning the front end.

so what happened was whoever ran new vacuum lines (years ago im guessing. owner of the truck owned it for 6 years and said 4x4 never worked) ran them wrong. the vacuum line going to the actuator was actually hooked into the vent hole on the vacuum switch lol so thats why it wasnt getting enough. so after routing it the proper way it works.