Took my posi all apart and was wondering : How do you know the clutch discs are worned out ?

Generally, new plates have a surface material that resemble exaggerated sharp mountain peaks....... So, if they are really worn smooth, and they will over time but not shiny smooth, they are toast.

 Also, there is a torque spec of about 45psi with the vehicle in park/reverse with a standard and one wheel sitting on the ground to break the posi loose. I will recheck the specs.

Thanks Vince, I will post pics after I clean the discs, the posi is out of the car...

Here are some pics of my DESTROYED posi unit including a cracked spider gear, now I can see the wear on the clutches comparing it to the tangs, elongated pin hole from wobbly retaining pin ! lol I've seen 3 broken small pin bolts over the years so far, I wonder why ? Weak point for these posis ???  

Most of the breakage come from people ramming their cars in R and D when they are stuck... Most instances, the spiders will weld themselves to the cross shaft pin, try to turn as a unit and finally breaking the bolt. The bolt itself, I believe, is a grade 8... 

 Was the pin and the inner surfaces of the spiders scored and worn??

 At least you can see what I mean about "good" and bad clutches...

Yes the pin and the inside of the gear were worned pretty bad...