So ive looked at all my vacuum hoses and such and all seems good as far as i can tell. Im thinking it is the possibly the vacuum motor.

Ontop of the front axle there is the vacuum motor and other stuff and one of them things is a Indicator lamp switch which is inline with vacuum motor. ill post a pic

I was wondering if the vacuum motor was to fail would the break and ABS light engage?

it used to come on after about five min of driving but it now comes on almost right away and i got no 4wd my front driveshaft spins but the tires do not

 

brake and abs light on is usually associated with bad rwal/speed sensor that inserts into the top of the rear diff.

if you have good vac at the cad on one line (for 2wd) and then the other (for 4wd), and its not engaging, then the shaft inside the cad that slides back and forth is probably stuck. remove cad and take it to the work bench and work the shaft free. you can artificially apply vac on the bench and see the diaphram move the shift fork. its actually a pretty simple device

 

Alright i will see if i can get it off. I just replaced the sensor ontop of the rear dif about 4 months ago and all was fine. but now ABS and break light are on again and i got no 4 wheel drive but front axle spins.....

 

i would ignore the brake/abs light for now. its a separate problem that's not really not hurting anything other than rear abs might not be working.

spray the 4 little cad bolts with a lot of pb-blaster. they're little and prone to snap if rusted up.

 

alright well i put it in 4L and 4H today and i felt the vacuum in one of the hoses that goes to the axle. So i followed them back to the tranny and i had vacuum in one of them also
So i followed them up(white and green) and the white one went to the left side of the motor and was working.

The green on in the other had went to the right side just next to the headers but it was not connected to anything. It is a Green hose going into a piece of plastic that is about the size of a nickel and looks like it goes somewhere.

But where does it go i cant see any holes for it but i can hardly see back there ?????

Its just hanging there but doesnt look broken or anything. Does it go somewhere in the back of the motor of on the side????????????????

 

take a look at the vac diagram on this page. only one of the vac lines from the t-case is connected to the intake manifold. the other one is a vent.

what you want to be sure of is that you have strong vac at the cad on one hose when t-case is in 2wd, and strong vac on the other in 4wd. if so, then vac is ok and your problem is within the cad.

http://www.dodgeram.org/tech/repair/..._engagment.htm

 

here's pictures of my vacuum lines on the engine.
https://dodgeforum.com/forum/2nd-gen...ml#post1545520