The oil sending unit on a 1985 Dodge truck is located on the
oil pan. However, the exact location on the pan can vary slightly depending on the engine (e.g., 318, 360). It's usually on the
passenger side (right side) of the oil pan, toward the
front.
It's a small, cylindrical unit with a wire connector. You'll likely need to get under the truck to see it clearly. Be aware that the oil pan will be hot if the engine has recently run.
