Why would my speedometer and rpm gauge stop working tranny acting funny to

Hello, sounds like you have an issue in the system that conveys information to the engine's processor regarding engine speed and vehicle speed. By accessing the information inside the engine's processor with a proper diagnostic tool, you will see if there are any trouble codes present directing you to the area where the problem is occurring for troubleshooting. A lack of signal to the speedometer is also a lack of signal to the transmission, so it is not sure what gear to use. A diagnosis will reveal areas of concern.