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Fleece Performance

Fleece Performance 03-07 Dodge 5.9L Cummins Coolant Bypass Kit (03-05 Auto Trans)

$397.95 $379.00 Save $18.95

SKU: F007 FPE-CLNTBYPS-CUMMINS-0305

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In Stock
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INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

It addresses the issue of insufficient coolant flow to the rear cylinders of the 5.9L and 6.7L Cummins engines, which can lead to high temperatures, excessive pressure, and potential freeze plug failure. This kit adds a secondary thermostat that operates based on temperature to maintain consistent temperatures across all cylinders, preventing pressure buildup before it becomes a problem.
Show original supplier description

Part #: FPE-CLNTBYPS-CUMMINS-0305

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.

Cummins Coolant Bypass Kit (2003-2005 Auto Trans)

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandFleece Performance
Part NumberF007 FPE-CLNTBYPS-CUMMINS-0305

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