4x4 problem
 

i got a 95 12 valve and the 4x4 is not engaging to the front axle. i pulled all the vacuum lines off and they are good no leaks. the red and green line do not have a suction to them idk which one is supposed to get the suction but both aint.Like i said though the rear end is locking and so does the front driveshaft:argh:

Maybe this will help.

Central Axle Disconnect (CAD) System Troubleshooting

its more than likely the tcase switch, when you engage the lever it turns on the vacum to the cad, if its bad it wont work.

yep, posi lock cable is a cheep, easy, and good fix

I have it an it's really nice to have. Just one less thing to worry about

I'd look into the cable, if I were you. Vacuum for lock was a bad idea on Dodge's part to begin with, if you ask me. Vacuum fluctuates, which means the it's possible that the lock will fluctuate in and out as well, when bumping the accelerator.

If you are not getting any vacuum you may have a cut line or your switch on top of the transfer case is stuck. Check you lines were they run up beside the front drive shaft thats were mine were rubbed into. I fixed it with a small piece of rubber line that slides over those lines and put some tape on them to keep them from being pulled off. I would go with the cabl lock also if it was going to cost very much money to fix. It is probably a cut line somewhere thought.

ok i got vacuum to the t case and if i take the main vac from the motor and hook it to the black vac line to the 4x4 then i got 4x4 and jus switch lines when i want 2 wheel drive. its somethin in the t case and i cant figure it out

that would work only problem is its just a pain to have to keep doing that.

buy a vacuum switch and hook it to a toggle in the cab thats what i did flip the switch to lock the hubs

The switch that screws into the top of the t case is messed up. Replace it and that will fix your problem.

i have fixed the lock collar with tacks on each side of it inside the axle. then disarm the fork. when you put it in 4 wheel drive she is in. :w2: no more vacuum to fool with and 4wd anytime anywhere when you pull it in inside.

x2 we just put the 4x4posi-lok one in my dads and it is awsome.no more problems. plus you get 2low(very cool)

Have the same thing on mine so far so good

Agreed. The posi lock cable is simple enough to install, and only about 200 bucks. You wont have to worry about 4x4 failing because of a vacuum problem again :tu:

i ran a two egr valves hook into the vacumm right out of the pump and they are wired to a toggle in the cab, only cost me maybe 40 or 50 buxs for everything at napa, works great and 2wheel low is nice for backing heavy trailers up steep grades

Take the vacuum control switch out of the transfer case. Then unplug the 2 vac lines that run down to the accuator. Start truck, see if you have vacuum on one of the 4holes on the vacuum switch plug- if you have vacuuum, hook vacuum control switch to the plug and press the button on the bottom of the switch while checking for vacuum on one of the 2 vac lines at the accuator. When you press and depress the button the vacuum should switch from one line to the other at the accuator. Mine ended up being a bad accuator. ($104+tax at Oreillys) vacuum control switch($17+tax) 4x4 indicator switch on accuator($4+tax) Hope this helps