Panache5000

Good morning Panache
I'm now fighting with the cone clutch of my sd50
Last time I've lapped it and after 900 hours now have the same problem
so now I've started to investigate as you did on the entire play on the axe.
I came to conclusion that the problem can be the wrong thickness of the various shims.
Do you know why the Collar Set Thrust 196320-04400 is not mentioned at all in the service manual, while all other shim thickness calculation is well indicated ?
(Ck Chapter 4.3 "shim selection" in the SD40-50 Service Manual)
Furthermore why this spare part is so expensive ?
Thank you very much
Marco