Coolant Bypass Kit Fit Dodge Ram 03-07 5.9L & 07.5-18 6.7L Cummins Diesel Engine. One of the biggest issues on the 24 valves is the coolant flow problem to the rear cylinders. This can cause catastrophic failure or blow outs of the freeze plugs in an over-temperature / over-pressure condition. Can effectively help eliminate the possibility of scored rear cylinders and blown freeze plugs for your 6.7 Cummins with this Coolant Bypass Kit, improves the reliability and longevity for Cummins platform. Specially designed to help lower coolant temperature at the rear cylinders, preventing damaging coolant pressure build up and ensuring consistent temperatures across all cylinders. Made from premium aluminum and Solid Steel with a black anodized surface enhances corrosion and oxidation resistance, more durable. Comes with high-quality AN o-ring fittings and AN hose connections with braided hose to ensure a leak free installation. 1 Coolant Bypass Kit. If you need return, please contact our customer service representative, let us know the detailed problem and send us some pictures for confirmation. We apologize for the late reply during the holidays.