A few months ago my 4x4 quit working but the light would come on. Then the light quit woking but the 4x4 would work. Last night I was pulling one of my Buddies out of the snow and I steped on the brake to get the limited slip to lock up, and my front-end went POP and the 4x4 light came on. Front driveshaft turns, but knuckles on the end of the axle do not. No strange noises. Also, same time as 4x4 light quite working so did the cruise control, I know i have a hole in the vaccume line and hope this has something to do with the 4x4. Maybe it will not engage the front end because it does not have enough vaccum and the add stress of the brakes made it pop out? Seems Like there are alot of people doing high hp boost launches on these frontends for something to break that easily?

Sorry for the Long Post
schaef

 

My guess is you should pop open the CAD on the axle and look in there first.
Could be something as simple as junk in the vacuum motor there that keeps the fork from moving where its supposed to.
Is your HVAC and cruise working ok? Sometimes a vacuum leak will affect the CAD.
If the front driveshaft is turning I wouldnt suspect the transfer case
Popping may have been an incomplete mating of the axle splines and the coupler. Id check this asap so youre not wearing out the splines

 

fix the vacuum line so theres no holes for starters since thats cheap.

 

sounds to me like your vacuum leak got big enough to disengage the CAD and kill the cruise.

the CAD axle will act just like you said if the sleeve at the CAD is not engaged. it takes vacuum to keep it engaged.

 

if you keep having vaccuum problems (I couldn't keep em from leaking) then my suggestion to you is to get the posi-lok kit. this is the cheapest around to the best of my knowledge http://cgi.ebay.com/ebaymotors/94-02...mZ280180130663 it also turned out for me that my vaccuum diaphram was bent. this kit is very easy to install as long as you follow the instructions. all that is needed to do the install is a 11/16 dril bit and some RTV sealant. i'm just throwing this out there as an option for a reliable alternative to the vaccuum controlled CAD. oops forgot... you will need a few wrenches and other basic hand tools.

 

You need to pop open the CAD cover and take a look and make sure that the collar and splines on the two axle shafts are looking alright. If they check out OK, then you need to find your vacuum leak. That pop that you heard could have been: Collar not engaged fully, thus stripping out the splines. Or... Collar wasn't engaged fully and slid off the shaft. Or... Shift fork somehow jumped out of it's groove on the collar. Or... some other mechanical failure in the CAD system. Bottom line is you're CAD system on the axle is the main suspect, and it's accomplice is a leaking vacuum hose.

 

Ok, thats kinda what i have been expecting, Its good and melted off now so I'll have a look see, I'm almost positive something is broke, probably the collar. Where's the best place to get front end parts?