The input shaft on my m47 is getting noisy. It is making a "tick-tick-tick" sound. It makes the sound while driving, and with the clutch out and the tranny in neutral. With the car at a stop is makes the sound with the clutch out in neutral, and it stops when you put the clutch in(you can hear the input shaft spinning to a stop). So is this the early sign of M47 failure? Is their any way to keep it going. How bad do they get? Should I be looking for a good m46 right away?

I have noticed mine doing the same thing on my M47. It sounds like this might be more common then I would have thought. I wonder if this symtom will eventually lead to transmission failure or if it is just a quirk of this transmission.

Hmm, mine's making a similar sound though rather faint.
Recommendations are to jack up the car on the side, and overfill the trans by a pint or so. Using a synthetic oil may help extend the life. Folks seem to love Redline MTL though I've not used it.
The M47 should always be filled to a higher level than you can achieve on a level surface. Some info about this in the 700FAQ.
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Rob Bareiss, New London CT ::: '87 244DL/M47- 221K, 88 744GLE- 202K, 91 244 181K, 88 244GL 145K