2nd Gen Non-Engine/Transmission 4 wheel drive not working

[grease man]

I recently bought a 94 2500 5 speed 4x4 the 4wheel drive used to work fine but since I had my u joints all replaced I noticed that It doesnt work any more

can anyone tell me what is the problem

 

[Steve St.Laurent]

On the passengers side at the back of the axle there are two vacuum hoses that connect to the housing which actuate a slider that locks the front end in. Check those hoses where they connect at the axle and follow them back to the transfer case and make sure you don't have something disconnected between the two.



Also, I'm moving this to the 2nd generation forum for better exposure.

 

[Glen Pratt]

I'd check the CAD vacuum actuator on the front axle (passenger side) first and make sure all the vacuum lines are connected. The CAD acuator might be bad. It's possible when they pulled the front axle shafts to do the u-joints they may have pulled off a vacuum line or damaged the CAD when putting the axles back in. You can either replace it or order a Posi-Lok which is a cable operated center axle disconnect instead of using vacuum. -Glen

 

[biggy238]

The speed at which you try to engage the 4wd will make a difference. Since this cold front has hit, mine won't engage without putting the truck into reverse and then back to drive. (hence no forward speed)