Had the same problem when the cable was very cold. Used white lithium grease on the cable. Fixed the noise and eratic needle.
Had the same problem years ago, found the drive cable was about 1/2 inch too long and put pressure on the speedometer head.

1954 Chevy Half-Ton
In the Stovebolt Gallery
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1958 Chevy 1/2-Ton Stepside
In the Stovebolt Gallery
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"Time's fun when you're having flies." ~~ OLD FROG