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Fleece Performance

Fleece Performance 03-07 Manual Transmission Cummins Coolant Bypass Kit w/ SS Braided Line

$397.95 $379.00 Save $18.95

SKU: F007 FPE-CLNTBYPS-CUMMINS-MAN-SS

In Stock
In Stock
Ships by Oct 23
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$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Fleece Performance Coolant Bypass Kit is designed to address the lack of coolant flow to the rear cylinders of the 5.9L Cummins engine, which leads to higher temperatures and potential freeze plug failure. This kit introduces a secondary thermostat that regulates temperature based on thermal conditions, not just excessive pressure. It ensures consistent temperatures across all six cylinders and prevents damaging pressure buildup.

The kit features a braided stainless steel water bypass hose and aluminum AN O-ring fittings for a leak-free installation.
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Part #: FPE-CLNTBYPS-CUMMINS-MAN-SS

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. 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.

Cummins Coolant Bypass Kit (2003-2007 Manual Transmission) w/ Stainless Steel Braided Line

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-MAN-SS

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