I have a 96 blazer and the four wheel drive is not working. Here is where my question begins, When I push the switch the transfer case ingages and it it the light switches showing me im in either 4 low or high. I jacked it up and put it on jack stands the front driveshaft is spinning when ingaged in four wheel drive but the front tires do not spin. Now last summer while driving down the interstate the four wheel dive kicked in on its own and made a terrible sound im assuming this broke something in the differential could anyone point me in any direction from here thanks in advance.

 

Sounds like the front axle coupler is toast, good time to do the bravada shaft mod.

 

I think I'll just put a whole new differential under it ive found some nice used one'smfor a couple hundred bucks so i think thats the route i'll go.