pulled inspection plate off to grease throw out - this fell out

I'm going to take a stab in the dark guess that's it is maybe an edge off the spline shaft. I wouldn't worry about it if it's working fine though.

 

Throwout bearing seal or ball retainer? Have you noticed any difference in sound when your foot is on the clutch? Let us know when you find out...

 

With no difference in sound, my next guess would be a portion of one of the clutch discs has come apart, could be a piece of steel between the fibers that broke off, maybe getting stuck in the process until it spun free... I would just keep running it and check it again in a few days and see if any more debree has come loose... Hang in there...

 

Piece of clutch disc. Clutch job in near future.

 

seeing some of the clutches we removed,and how utterly beat up they were,yet working just fine...i wouldn't waste 2 seconds worrying about that piece after looking for and finding no obvious damages.

 

Oh i not saying pull it. But do it before it scatters. Normally when you have engagement problems, or dampner spring broken and laying in bottom. But for me if its a fleet truck i pull them at first sight of problems. My way of controlling down time. Now with my own truck. I might worry my butt off and run it a bit. But id rather pull it early with scheduled down time versus unplanned down time. If you have never seen a 15.5 clutch scatter, you dont wanna. Ive replaced customers flywheel, flywheel housings, starters, trans input shaft, clutch housing, wiring harness. Floor pans, and one time it took out trans case. Did one that ended 18k to put it together. So on my truck. I have no problem throwing away a half used clutch.

 

I had a spring come out of the clutch disk one time. It had some spare parts that looked like that. It looks like part of the retainer the holds the springs in. The pedal would not depress like you say.
I almost ran a ground guide over that was not paying attention. I was backing slowly down hill and had to blip the throttle and jerk it out of gear. I sat there and played with the clutch pedal for awhile and was able to get it working long enough to get it to the shop. The shop had a big pile just like it said it was an Eaton issue. They installed a Lipe disk and an easy pedal Eaton pressure plate.