i have a new speedometer cable and new speedometer gear tooth. my speedometer needle moves around and isnt steady like it should. from 0 to 40 it works like it should and my odometer works, but after that the needle rocks. i can tap on the glass a few times at it goes back normal for a while.
do i need to get a new speedometer? what can i do to fix this problem?

 

I'm assuming it's your 66?

What do you mean...'needle rocks', and you can make it go back to normal for a while? When you tap on it, it stops oscillating and stays steady?

Sounds like you need to lube your cable first and see what happens.

 

yeah a 66 coupe
when i say the needle rocks: the needle sways from 40-50 and i know im going 45. when i tap the glass the needle stays steady for a bit then starts swaying again.
what type of lube do i use?

 

Go to the auto parts store and tell them what you need. They sell a graphite based lube just for this application. You pull the cable out, cover it with lube, and reinsert.

 

i have graphite powder. and i have white litumim grease. they told me to use the graphite powder. but i dont think it is going to work