Year of truck?
All dash lights are on the same circuit. Different year gauge clusters implement the bulbs differently but they all share the same problems. Bad contact with the bulb, either ground or power. Remove the negative battery cable, remove the gauge cluster, remove the dash bulbs and clean them and the socket contacts. Then clean the fuse block contacts and bend the fuse clips so they make better contact. Make sure the gauge cluster is grounded while testing. The screws that mount it provide ground.