ok so my rear diff u joint grenaded on me today, so i pulled the rear shaft off and thought i could baby it home in front wheel drive when ALL OF A SUDDEN the front shaft just spins lol but not turnin the wheels , i was able to get out of the truck with it in 1st gear and watch the shaft just spinning away. the truck is a 96 2500 so im aware there is a vaccum system on this but where and how is the best way to identify where the leak or break is? where is the hoses for this system? ive always had manual locking hubs on my other trucks so this vaccum system is new to me, any info appreciated!

 

There's a bunch of places that leak could be really. When mine did this I just bought a posi lock kit. I don't have the patience to hint down a vacuum leak.

 

mine had no 4x4 when i bought it, and it turned out to be the little one inch lines that go into the CAD, replaced that ($1.50 in parts) and then i had 4x4 again, been off roading a thousand times since, and no problems.....and the lines didnt even look bad.....a pinhole can cause this problem.

 

cool man thanx! by the way, whats a CAD?

 

Central axle disconnect. It's thing on the passenger side of the axle. It's a fork that slides a collar over to engage the axle.

 

so how did you get it home i kno a kid that used his shirt and his belt and was able to make it home... at least thats his story i did not witness it

 

yes for the CAD, look at the back of the front axle on the passenger side, Its the only thing popping out of it.

 

thanx guys ill check that out, i had to get her towed. now i gotta begin work on gettin the rear end all centered and aligned properly . damn. im gonna post another thread on info for that. basically i gotta cut the ubolts off (they bent under the torque) and get everything centered again. the yoke is pointed damn near straight up and the axle twisted sideways a bit . you guys ever swapped a rear end? ive done it once but had help and many beers that day, fuzzy memory on that job. i know side to side i gotta measure from frame rail to drum but front to back i cant remember how, measure off quarter panel corner to center of wheel maybe? and then theres the yoke, do i hook up driveshaft first , get it in a straight line to the transfer case or is there a tool i should get to measure proper degrees?

 

I didnt have 4 wheel drive when I bought my truck, just turned out to be a clogged vac line on the CAD. there should be a little bit of a pinion-driveshaft angle. see if I can find anything more specific...

Edit: typical u-joint configuration.

 

http://s1212.photobucket.com/albums/cc460/acewyatt/ is the link to my photobucket album of the rear diff. gonna be a bit of a job lol