Condition Price Qty  
Very Good $19.00
This is the original wiring diagram printed by GM 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. Although the schematic is in black and white, the color of each wire is noted. You will not find this diagram in your shop manual. The schematic measures 8.5" x 11" when folded up, and opens up to 11" by 38". The diagram pictured is an example of this type when folded, but is not the actual diagram for your vehicle. Buy now for the best electrical repair info - the factory wiring diagram.
General Motors
1978 Truck Wiring Diagrams MD17218
Write a Review
Covers the General and Bison, also known as N9 with 6V-92, 8V-71, and 6-71 Detroit diesel. To verify that this is the correct diagram for your truck, you can check your VIN code. The 2nd digit should be either an M or an N for the aluminum conventional cab, the 3rd digit should be H, I or J to indicate Detroit Diesel. The 6th digit should be an 8 to indicate 1978.
1978 Chevrolet Bison
1978 GMC General
1978 Chevrolet Bison 1978 GMC General