HVAC Blend Door Actuator. HVAC Air Door Actuator. AIR DOOR ACTUATOR. 2003-2006 GMC Sierra 1500 Temperature; Position: Lower Main;. 2003-2006 GMC Sierra 1500 Temperature; Position: Upper Main;. 2008-2013 GMC Sierra 1500 BodyType: Standard Cab Pickup; Air Inlet; Position: Main;.