Speedometer works sometimes, and sometimes stops working on 1994 Buick Roadmaster

I recently had the car to repair shops and they replaced a sensor over the rear axle, another mechanic checked a device in the transmission and said it was OK. What else could cause the speedometer to work intermittently?

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1 answer
There could be a corroded wiring connection, for instance. Also could be the dash gauge failing. Sounds like you need some help, here's a directory link for you:
http://repairpal.com/directory?address=78263&car_brand_names=Buick