overdrive question

["david orcutt" <dorcutt@total.net>]

Help,  The over drive on my 75 tr6 fails after it is warm apr. 10 to 15
minutes of operation.  I pulled the filter and found a fair amount of fine
metal in the cover.  Changed the fluid and drove, still inop.  Changed the
solenoid with a good one some lent me and she is ok.  Pulled the filter
again and still found some slight metal in there.  Not much.  I'm going to
replaced the solenoid but don't know if some metal is some what normal.  Any
one have any thoughts?  Thanks.