Prepare your semi truck to be Ready for the Road Ahead , with the Maxon 4-Post Solenoid Assembly that offers precise control of mechanical components. With an easy to install design, this replacement solenoid is the ideal option to help monitor the processes of engine ignition, fuel injection, braking, suspension, and more. Built with top-tier materials to deliver long-term reliability. FleetPride is your First Click in Heavy Duty .