This is new for this truck. After driving the truck up to Deland and back last night - I bring it in - and clearly notice a light rattling sound under the drivers side. This is parked idling in neutral. Push the clutch in - rattle goes away. Let clutch out in gear - rattle goes away. Leave it idling in neutral with clutch out - rattle is there. Suspect I'm going to need to figure out what this is. Any input or guidance? Greatly appreciated. update - this morning, start the truck cold - no noise. nothing. so it's heat related.