Sounds like sticky glue off of the stop pins is your problem. Take the cluster out and take the front glass off. Use some acetone on a rag and wipe the pins off. The glue starts to run in the summer causing the needles to stick to them. Then it comes loose from jarring. The speedometer comes free due to the torque applied to the needle the faster you go. Good luck and take your time!!

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THANKS.
I'll have my repair try that.