Next time take your speedometer to a speedometer shop. I had the same sort of problems with my speedometer like failing trip tick and then mileage numbers would be pushed off the gears. I tried all sorts of tricks to get them to work but without success. I finally took it to a speedometer shop and he knew immediately that it was age and the lubrications in it had dried up. He said the lubrication was toxic and not off the shelf (what I put in it made it worse) and all he had to do was clean it out and re lube. He even replaced a gear I took out to separate the trip tick as one of my attempts to get it to work. (I still had the gear and gave it to him afterward). It only cost me $64.20. Been running smoothly for years since.
 Bill H.

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