In the maintence manual it just states inspect and replace the gasket if necessary, the only sealant that is listed for the motor is Silicone Gasket and Sealant F7AZ-19554-EA, Spec. WSE-M4G323-A4 But it does not give any indication that it is used on the Lower Intake manifold assembly.
It is not regular silicone. I have the information you want at home so if nobody else posts between now and later this afternoon I will post it for you.