The other day I needed my 4-wheel drive and needless to say it did not kick in and I was stuck. The transfer case is shifting into gear fine and that's why I thought the 4x4 was working, The axle is just not engaging. The vaccuum lines appear to be fine and after about an hour of fighting the mud it kicked in and I pulled right out, after unhooking the stock trailer. Later that day I had to go back in and pull out my trailer. It took about 10 minutes before the axle finally engaged, pulled the trailer out just fine. Now my 4x4 light still has not gone off but the axle does seem to have disengaged because I feel no tension when turning. Any Ideas or similar problems from anyone else?
Thanks
Luke

 

I had a similar experience, and had to really search to find the vac. leak. it was bundled up along the edge of the fire wall but once I replaced the cracked vac line with a fresh one, I have had no problems hooking up.

 

Thanks for the input markman. Where at by the firewall do the vac lines come up? I've looked for vac diagrams but have had no luck. Thanks again!

 

it could be the axle drive motor if it gets bent or even age will cause a leak in the diaphram and act like that . my 01 was doing all the same things I ordered a new moter from quad 4x4.com and it works great now.
R

 

The vac line runs through the loom of wires along the edge or top of the firewall. I looked at the joints and connections first but found a cracked line hidden in the loom.