No metal shavings, just what appears to be drag mechanisms.Doesn't appear to be the kind of failure mechanism found in S3-S4.
one quick question: isn't it possible to do more frequent controlls of both SARJs by station crew EVAs?
If you mean inspections, yes it is possible and it probably become more commonplace with future EVA tasks if there is a concern about P3/P4 SARJ wear.