I need wiring diagrams for a 1981 Ford truck f-250 - ASAP Jan 01, 2010I need wiring diagrams for a 1981 Ford truck f-250 - Answered by a verified Classic Car Mechanic hi there i did find the one for your truck your will see 1979 but they are identical don 1981 ford f-250 wiring diagram . Don, Classic Car Mechanic. Category: Classic Car. Satisfied Customers: 1,747. ford f250: I lost my dash lights and all 1981 Ford F100 F150 F250 F350 Pickup Truck Foldout Wiring This is the original wiring diagram printed by Ford for dealer mechanics. You can follow the wiring in your truck from bumper-to-bumper. It will help you to understand connector configurations, and locate & identify circuits, relays, and grounds.