When I bought the truck the lightbulb for the gas gauge and the speedometer was out. A last week I replace them and after that I started having weird problems with my instrument cluster. The engine light or the traction control light would come on and tell me there's a problem but everything else works fine. It didn't seem to affect the truck. I could just turn off the engine turn it back on and be back to normal. That went on for about a 3 days. Then everything was fine. Well this morning I noticed that the tach has stopped working. Checked all the fuses checked everything I could think of. I'm not sure why it stopped working.