Clutch Sounds in 4KQ

[Thomas Alexander <thomas@edu15.coe.ufl.edu>]

Just returned from a 1000 mile trek in my '86 4KQ.  When I pulled into
the garage,  I heard an awful metal grinding sound when I pressed down on
the clutch.  The car still runs fine.  As well, the sound is not present
when the car is sitting still idling in neutral.  The car has about 140,000
miles and has its original clutch.  

Please advise whether this is being caused by the clutch or a part within
the clutch.  If you know of rough estimates of prices, that would be
great too.

Regards,

Thomas Alexander