Dave,

I am NOT an expert with Mustangs, but I do know that the T/O bearing is NOT 
SPINNING in a TI/TII configuration, UNTIL the clutch pedal is depressed...  
When the clutch pedal is depressed, it puts tension on the clutch cable, which 
in turn, pulls the lever attached to the T/O bearing forks, which, in turn, 
presses the T/O bearing against the pressure plate ring (or fingers), thus 
releasing the clutch disk....  When the clutch is disengaged in a TI/TII, the 
T/O bearing does not spin as it is hanging on a set of forks and does not 
engage the output shaft from the tranny.  It is entirely possible that the 
Mustang T/O bearing spins w/ the output shaft, unlike VWs, thus creating the 
bearing noise you had to repair in your Mustang.   

I've been wrenching on these puppies (TI/TII) for over 25 years and have NEVER 
heard a T/O bearing make noise without having pressure applied to it via the 
clutch pedal.  I have, however, had a number of trannies that have final 
drive/input carrier bearing noise as they get worn....  Another potential area 
is the Ring & Pinion carrier....  when the tranny gets worn, the backlash 
setting gets out of whack and you get gear noise from the R&P...... JMHO

       Jon
       1950 DeLuxe Beetle
       1958 Karmann Ghia Coupe'
       1959 Karmann Ghia Cabriolet
       1960 Beetle Cabriolet
       1971 (Original Owner) Super Beetle
       1986 Jetta GL
       1990 Syncro Westfalia
Jon Peters/UB Networks writes:
> 
> I beg to differ on that point...  when you push the clutch in, you take the 
>load off of the input shaft of the tranny.  Once the load is off of the tranny 
> input shaft, it stops making noise.  On the other hand, if the T/O bearing is 
> going out, the noise only occurs when you disengage the clutch (push the 
> clutch pedal in).  
> 
> I still stand by my original diagnosis of the input shaft carrier bearing 
> being worn!!

Jon,
 I beg to differ.  :)  My mustang has a sqeaky throwout bearing which,
under no load (i.e. pedal OUT) whistles annoyingly.  When I push the pedal
in a little, the load that is put on the throwout bearing quiets it.  I did
the clutch replacement myself, and am very familiar with how things operate
down there.  FYI, the throwout bearing was a low-bid item bought at auto
parts club.  Next time I'm going Napa.

I'm not trying to say that your diagnosis of the input shaft carrier bearing
is wrong, simply that there are other likely possibilities.

One more thing, there should never be any load on the input shaft of the
transmission (only torque applied to it).  

-David

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David Schwarze                  '73 VW Safare Custom Camper (Da Boat)
SAIC Comsystems                 '73 Capri GT 2800 (Da Beast)
San Diego, California           '87 Mustang Lx 5.0 (Da Bruiser?  Soon...)
schwarze@nosc.mil                http://papaya.nosc.mil/~schwarze
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