I am having a problem with my speedometer. It doesn't work correctly on 1993 Lexus SC400

The speedometer bounces all over. It registers 80 when I am doing 35, and it will stay at 40 when I am stopped. I am at a loss why it is malfunctioning

Asked by for the 1993 Lexus SC400
Most likely the speedo head needs to be fixed/replaced. That fixes the Toyota's so it should work here too!