Transfer Case
WARNING: This page is about a different car, the 1990 Dodge Ram Wagon, 1990 Dodge Ram Van, 1990 Dodge Pickup, 1990 Dodge Dakota, and 1990 Dodge Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
With vehicle in level position, remove filler plug and check fluid level. Add lubricant if level is below bottom of filler plug hole.