speedometer sticks

I have a 76 L-48 automatic. The speedometer does'nt work. It stays at 30 mph. If I unhook the cable at the speedometer it goes back to zero. Has anyone had a similar problem or any suggestions?
Zeeth

at the trans disconnect the cable and try to spin it while looking at the speedo to see if it works. let me know

at the trans disconnect the cable and try to spin it while looking at the speedo to see if it works. let me know
rickwhoo- thanks. I put a new cable in the car. It seems to work pretty good. It does go up fairly smooth now, but it drops at 5 or 10 mph intervals. Maybe thats as good as it's going to get. I appreciate your response. Thanks again !
Now I'm hoping for a response on my power steering problem. This is where I spent a lot of money wih no results.

make sure the cable is lubed

Thanks Rick ! I'll do that and let you know. Zeeth

What should I use for lube ? graphite ?

i used to use white lithium grease.

Thanks Rick I used some JB 80 and it seems to be working smoother the more I drive the car. Now I have to concentrate on my power steering problem. Thanks again for your interest and help.
Zeeth