[Sirrotica]

I've taken them apart when the only thing left is the outer race. The grease gets hard from age and the inner parts disintegrate. The balls, and inner race were MIA, and a lot of metallic dust is left. The outer race was the only piece that didn't fall apart, still stuck in the crank just like when it was installed. I can't remember if the input bearing was bad in the transmission on that one or not. Too many clutch jobs to recall each one in detail.

All I can speak for is, it definitely helps if you give the bearing a little extra grease. They seem to stay together much better, than just hoping there was enough grease when assembled by the manufacturer.

The Pontiac pilot bearings are fairly unique, most manufactures use a bronze bushing. I have seen a few trucks that use a ball bearings, but not many cars. Trucks however sit at a stop with the clutch disengaged, and if you don't have a cowboy driver, the clutches in trucks tend to last longer so maybe it was a durability reason that Pontiacs used it...can't say for sure. GTO clutches never lasted very long....LOL

I never worked on any stick shift older cars with the straight eight, or sixes from Pontiac, so not sure how far back they used the ball bearing pilot bearing.

A roller bearing would probably be more robust, but with little side loading, probably not necessary. If it gets replaced with every clutch replacement, it's probably adequate, as long as the grease doesn't dry out.