My speedo works on and off. The needle might return to 0 or it might land on 20,30, or stay stuck on 50. When it works it's fairly stable. I have a new cable. Is there something I can do to fix this problem? Forgot to mention the Odometer works good.

Mine did a similar thing but after changing the cable it was fine, well fine after driving regularly. If you dont have oil walking up the cable it may be just some dirt built up on things inside the speedo. It is easy to check the plastic gear in the trans.

I had a similar problem with the needle bouncing, when the tranny was rebuilt it stopped. So I'm guessing my problem was the gears. Moral of the story- check everything.