Genuine OEM GM 40009452 Engine Coolant Flow Control Valve 3.0L Duramax Diesel

The LZ0 Duramax diesel engines feature an advanced Active Thermal Management (ATM) cooling system designed to optimize fuel economy, performance, and emissions. This Engine Coolant Flow Control Valve plays a critical role by precisely controlling the coolant flow from the water pump, ensuring peak efficiency in all operating conditions. It combines a rotary control valve and a block control valve to independently manage coolant flow during warm-up (split cooling), eliminating the need for a traditional thermostat.

The valve directs coolant to critical components such as the turbocharger, EGR system, oil coolers, and heater core to efficiently regulate temperatures. The system also includes a de-gas circuit to remove trapped air, ensuring optimal operation.

Replaces: 40009158

Fitment: 2023-2025 Chevy/GMC LZ0 3.0L Duramax Models

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