Replace the gauge.
This problem indicates an un-repairable failure inside the unit.
This has happened several times to me... Turn Key to OFF position Hold in the Trip Odometer Reset Button Turn Key to ON This will force a instrument panel self check and the speedometer needle will correct its self. If that doesn't work the dealer can recalibrate the cluster to get the needle in the proper place.
I know the dealer ship scan tool can be used to reset the speedometer.
why is a nonelectronic speedometer needle bouncing
If it's an electronic (analog) speedometer needle, you probably have a problem with the dasboard grounding.
The only place you could get just the needle is a salvage yard.
You are not moving!
it's asleep
Send to a speedometer repair shop or replace speedometer head
I didn't know my car was going 72 mph because the speedometer broke. The needle on the speedometer bounced whenever I hit a pothole. The speedometer's needle was stuck at 15mph. Before I could glance at the speedometer, the policeman's radar gun clocked me going over the speed limit.
Sometimes a clicking or grinding Sometimes speedometer needle will fluctuate
If the speedometer needle is going crazy and not working properly, it is probably the speedometer mechanism that needs to be replaced. It could also mean the vehicle is having a transmission slippage problem if the needle is bouncing back and forth.
use spraypaint or fingernail polish