We’ve been rebuilding these units since the 80’s
There is a lot of misinformation on the internet about this subject so we thought we should publish what we know.
Under normal use and with good maintenance, G80’s typically only wear out the clutches on what we call the “thin” side
Early G80 used steel clutches on both the thick and thin side
In an effort to reduce maintenance intervals, GM switched to carbon fiber lined clutches on the thin side in the mid 90’s
All of the carbon fiber clutch disc lineups have less active surfaces than the steel clutch versions of the same axle type.
In the early 2000’s the fuse disc lineup was also replaced with a carbon fiber unit. This facilitates a change in the ramp plate to accommodate the thicker lineup. Not all the differentials were changed at once; this change was phased in over a period of a few years.
Below are some examples of worn out and mechanically damaged clutches (scroll through pictures)
Good eared fuse disc 
Good used eared disc (top) Mechanically damaged disc (bottom) 
Mechanically damaged disc 
Worn out internal eared disc (not usable) 
Very worn disc – note the large step and almost no cross hatch remaining 
Very worn disc – note the large step and almost no cross hatch remaining 
Very worn disc – note the large step and almost no cross hatch remaining 
Very worn carbon fiber disc – note the carbon fiber flaking off
See our writeup on G80 operation to explain what a fuse disc is intended to do.
When a fuse disc strips, it usually wipes out the governor and ramp plate
Here are some examples of some good and stripped “fuse” discs
