Fleece Performance 04.5-07 Dodge 5.9L Cummins Coolant Bypass Kit (06-07 Auto Trans)

Increased Coolant Flow, Decreased Coolant Temperatures The rear cylinders on the 5.9/6.7L Cummins suffer from a lack of coolant flow, and therefore, experience the highest coolant temperatures. This can cause excessive pressure to build in the cooling system, especially the rear of the block and blow out freeze plugs externally, or the smaller diameter plugs under the valve cover, leading to a failure. Our coolant bypass kit adds a secondary thermostat, that unlike other brands, works based on temperature instead of excessive pressure. This solves the problem before pressure becomes an issue by ensuring consistent temperatures across all six cylinders. Benefits: Lowers coolant temperature at the rear cylinders Ensures consistent temperatures across all cylinders Prevents damaging coolant pressure build up Complete kit comes with braided hose and AN O-ring fittings to ensure a leak-free installation. Kits for MY 2003+ include billet hose brackets. Why do I need a Fleece Coolant Bypass? One of the biggest issues on the 5.9/6.7L Cummins 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. The Fleece Coolant Bypass is one of the most important additions you make to improve the reliability and longevity of the Cummins platform. The '03-'07 5.9L automatic transmission version will eliminate the factory transmission fluid heat exchanger. The heat exchanger is not a fluid cooler, it was designed for use in cold climates to warm the transmission fluid with the engine coolant. It is not necessary for use in warm climates or high horsepower applications, nor does it detrimentally affect the trucks performance when removed. All 07-13 6.7 trucks, both automatic and manual equipped transmissions, do not have a transmission fluid heat exchanger.

Part Type

Engine Coolant Bypass Kit

• Complete kit comes with braided hose and AN O-ring fittings to ensure a leak-free installation
• Ensures consistent temperatures across all cylinders
• Lowers coolant temperature at the rear cylinders
• Prevents damaging coolant pressure build up

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Product Downloads

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1.	Installation Instructions

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Reference Information

COOLANT BYPASS KIT, CUMMINS (2006-2007 AUTO TRANS)

Fleece Performance coolant bypass kits meet the demands for more cooling that comes with increased horsepower. Your engine cooling system was designed to handle a 300-350hp engine. When you increase the power, you increase the demand on your cooling system and the possibility of problems that may lead to failure. Fleece coolant bypass kits feature a secondary thermostat that operates on temperature--not excessive pressure--solving excessive pressure problems before they become an issue by ensuring consistent temperatures across all six cylinders. Each kit includes high-quality AN O-ring fittings and AN hose connections with braided hose to ensure a leak-free installation. When there's a need for better performance, you can rely on coolant bypass kits from Fleece to supply the necessary components for assured greater performance.