Well my 4wd is not working yet. I have checked, rechecked and re-rechecked all vacuum lines and everything looks good, I pulled the CAD off today to watch the shift fork and it is not moving enough about 1/2" sometimes. My question is this...I can pull a vacuum on the cad if I block the opposing connection off, but I can not pull a vacuum on one side or another without blocking off the other side...my thought is that the diaphram in there is leaking. Could this be?

 

Going off memory here so this could be dangerous. At the CAD, truck running, you should have Vac at the red line in 2wd. 4X and there will be vac at the black line. Use a gauge for this and compare the reading to what the vac pump is putting out.

 

jriggs,

Not sure which one it was but one of my lines was totally blocked and acting similar.

Ended up replacing the whole mess with a manual cable....much better with the added benefit of 2wd low

Cheers,

ftr

 

sound like the diaphram is leaking, I just finished fixing my 4x4 light issue, and mine would shift back and forth with my hand held vac pump and it would not leak between ports

 

nick-if your good part would not leak between the two parts I think that confirms that it is my faulty shift motor. So now my ? is what are my posi lock options? or where can I get a aftermarket replacement for cheap?