Discover the essential 1985 Medium and Heavy Duty Truck Wiring Diagram X-8560A, a must-have for GMC vehicle enthusiasts and restoration experts. Published by General Motors, this detailed paper chart provides a comprehensive overview of the electrical systems in your truck, making it an invaluable reference for maintaining or restoring your classic ride. Proudly manufactured in the United States, this wiring diagram is a testament to the quality and durability expected from the GMC brand. Whether you’re tackling a restoration project or simply want to enhance your understanding of your truck's electrical components, this diagram will serve as an indispensable guide.