Cooler Bypass Delete 17-19 GM Allison

The Cooler Bypass Delete for 2017-19 GM Allison transmissions eliminates the factory transmission cooler bypass valve system, allowing full flow through the transmission cooler under all operating conditions. This modification is designed for builders and enthusiasts who operate modified or heavily loaded trucks where stock cooling capacity falls short of real-world demands. The bypass delete forces continuous coolant circulation through the cooler, preventing the transmission from operating at elevated temperatures during towing, high-load hauling, or performance driving.

BD Diesel engineered this bypass delete kit to maintain consistent transmission fluid temperatures by removing the stock bypass valve that typically diverts cooler flow during cold-start conditions. The compact design fits seamlessly into the 2017-2019 GM Allison transmission cooling circuit without requiring extensive plumbing modifications. By ensuring full-time cooler engagement, the kit reduces thermal stress on the transmission fluid and internal components, extending transmission lifespan under severe duty cycles. The one-pound unit integrates directly into the existing coolant passages, making installation straightforward for technicians familiar with transmission cooling systems.

This product benefits truck owners running tuned engines, upgraded turbochargers, or increased fuel delivery on 2017-2019 GM trucks equipped with the Allison transmission. Heavy-duty operators—including those towing gooseneck trailers, car haulers, or operating in extreme climates—will see measurable improvements in transmission stability and durability. Installation is compatible with stock cooling systems and aftermarket coolers alike; however, ensure your cooling system capacity is adequate before eliminating the bypass function. Pair this delete kit with a quality transmission cooler for optimal results in high-performance or severe-service applications.