so i just bought this truck last month and ive noticed the speedo has been acting up. its happened twice now, first time the needle was about 20 mph slower my actual speed and this most recent time it got stuck at 30 for a while and then started moving but was 30mph over my real speed. the first time it happened all i had to do was pull over, shut the truck off and turn it back on and it was back to 0. this most recent time i had to run the gauges sweep to get it back to 0.

has anyone had a problem similar to this and can give me a good starting point to start checking things? it sounds like its a problem in the actual speedo dial but id like to be able to confirm that before i buy a new one.