You can take a car or motorcycle on many ferries from Naples to Sicily, including routes to Palermo, Termini Imerese, and Milazzo. Operators like GNV, Grimaldi Lines, Siremar, and Tirrenia offer vehicle transport. When booking, you’ll need to reserve a vehicle space ahead of time (especially in high season) because car decks fill up fast. Your vehicle will need proper registration documents. Note that there are no direct ferries from Naples to Trapani at present, so even if you plan to bring a car, your journey will likely involve disembarking in Palermo or another Sicilian port, then continuing by road or local ferry to Trapani.