Dorman 600-490 4WD Actuator

4WD Actuator Upgrade for GM Trucks

Dorman 600-490 is a 4WD actuator upgrade kit for older Chevrolet and GMC trucks that use a thermal differential actuator. It replaces the slower wax-based design with an electric actuator setup for more responsive 4WD engagement on supported GM applications. This kit is built around the Dorman 600-101 electric actuator and 600-600 actuator harness for a direct update to the original thermal system.

• Upgrades older thermal differential actuator systems to electric operation
• Includes a 4WD electric actuator and matching wiring harness
• 3-terminal connector design with rectangular connector shape
• 98.5-inch wiring harness length
• Plastic housing construction
• Four Wheel on Demand conversion: Yes

How This 4WD Actuator Works

On many 1988-1996 Chevrolet K1500, K2500, and K3500 trucks, as well as 1992-1996 GMC K1500, K2500, and K3500 models, the origi