1973 cadillac deville speedometer issue

[timman126]

I was wondering if anyone had an idea of different speedometer fixes. My speedometer bounces all over the place so i figured i would replace the speedometer cable. I did and it still does the same thing. Any ideas?

[Scot Minesinger]

I would have thought for sure that the cable replacement would cure the problem too. 

Do you have cruise control and replaced both cables?  If yes and only replaced one speedometer cable, then replace the other.  If it has cruise and you replaced both cables then it could be the cruise unit that receives the two cables.

You can check the plastic gear (and section that receives the cable to make sure it is not worn and slipping-square female connection-check to be sure it is not rounded) at trans connection and make sure it is good, only other option seems to be speedometer itself.

[timman126]

It doesn't have cruise control. I pulled the gear from the transmission and it doesn't seem to be worn down.

[bcroe]

Your speedo needle has 2 bearings, one in front.  The other is in back, right in the center of
the rotating magnet assembly the cable drives.  If that bearing gets dry enough, it can try to
grab the needle and throw it higher.  Unfortunately adding lube means taking the speedo
completely apart.  Bruce Roe