GMC K3500 Wiring Harnesses & Electrical - OEM-Fit Harnesses & Components
Restore your GMC K3500’s electrical system with precision-engineered wiring harnesses and electrical components designed specifically for your vehicle. Each harness is manufactured to match the original routing, connectors, and circuits of your GMC K3500—restoring the wiring behind the dash, under the hood, and through the body to factory-correct, or factory-improved, condition.
Our GMC K3500 electrical lineup includes complete wiring harness sets, battery cables and ground straps, switches, electrical devices, and update/conversion products such as alternator upgrades and electronic ignition conversions. Every component is manufactured and tested to deliver dependable, factory-correct performance, and is organized by your vehicle’s exact year to ensure the harness or component you order is the one built for your GMC K3500—not a close approximation.
Use the Vehicle Selector above to find the correct wiring or electrical component for your GMC K3500, or browse below to explore available options. Whether you’re chasing judging points with a numbers-matching restoration or simply getting your GMC K3500 running right, Factory Interiors makes it easy to restore your electrical system with wiring products proudly made in the USA.
-O.E.M. made in U.S.A. using original GM/Delco tooling-, (includes wiring)
use with 700R4 or 2004R automatic trans. EXCEPT 4L60E or 4L80E. Completely externally installed kit allows for automatic operation of the torque converter lock-up (overdrive) without installing the computer!!!! Kit includes instructions.
1973-1987 GMC K3500 Classic Update Series Alternator Conversion Harness, built to original specification.
- Choose your exact application from the options above
- Each option lists the equipment and fitment it covers
for use only with our RestoMod Series wiring system, should your Mega-Fuse become damaged or in need of replacement. NOTE: 2 of these Mega-Fuses are already included with our Classic Update Series wiring system.
Manufactured specifically for 1973-82 models. Designed with the foresight, engineering, and flexibility to bring your electrical system up to date. Choose the routing of the wiring to fit your needs and accommodate all of the most popular custom/aftermarket and reproduction/original accessories available!!!! Includes many of the vehicle's basic electrical devices and detailed instructions!!!!
(87 Total Products)