i was playing in the mud last week, in 4wd, i threw it in 2 so i could throw some mud around, i went to put it back in 4 and started to crawl out, it was working until i heard a loud metallic pop, and i sunk back into my ruts. the transfer case will engage, i can feel it click, but the front tires dont spin for me, i felt the front diff and it was still cool, i also heard that there is a vacume system to enguage the front diffs, does anyone know or have a guess of what it might be?

 

Check your front driveshaft.

 

X2

 

Have some one else drive it very slowly with the 4x4 engaged and look under to see if the shaft is turning. If it is then its in the axle. If its a vacumm system then you should try to locate the line and make sure its not broken.

 

Or just crawl under the bastard and grab ahold of it. I broke 2 stock front shafts, one on stock tires, and the other with my 36's. They are easy to snap, especially if you are trying to rock the truck back and fourth, or if the front end starts hopping. I eventualy got smart and had one made out of thick wall tubing.

The front driveshaft is the weak link. The next weak point is the halfshafts/CV's, but if you broke one of those, you would hear it when your driving. The front driveshaft only turns when 4wd is engaged.