I have a 4.9L straight 6 and my battery voltage gauge and my gas gauge aren't working the gas gauge is stuck below empty even after I filled up and sometimes the battery gauge will slightly fluctuate any ideas what may be going on?

 

Have you pulled you cluster to make certain the wiring hasn't came unplugged? I have issues with my alternator not charging and gauge reading low. Light tap with fist on the dash above cluster and alt starts charging and gauge reads right. I still have yet to tear into mine...