The speedometer is not functioning properly. The gauge is reading 40 MPH higher than the actual speed.
One thing that can cause a problem with the speedometer is the output shaft speed sensor. The sensor and wiring should be inspected as this item can send an erroneous readings to the engine computer. If there are no issues with the speed sensor then a new instrument cluster may be necessary. There is a sweep test for the instrument cluster to check to make sure the functions of the cluster are working. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have access to the wiring, diagrams, tools and knowledge of the speed sensor circuit and instrument cluster. They will be able to diagnose your speedometer issue and assist in the repair of the instrument cluster.
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