Home / Shop / Fleece Performance 03-07 Dodge 5.9L / 04.5-12 6.7L Cummins Coolant Bypass Kit (03-07 Manual Trans)

Fleece Performance 03-07 Dodge 5.9L / 04.5-12 6.7L Cummins Coolant Bypass Kit (03-07 Manual Trans)

SKU: FPEXFPE-CLNTBYPS-CUM-9HPT

Water Bypass Kits

FPE Coolant Bypass Kits...

Fleece Performance

Fleece Performance 03-07 Dodge 5.9L / 04.5-12 6.7L Cummins Coolant Bypass Kit (03-07 Manual Trans)

SKU: FPEXFPE-CLNTBYPS-CUM-9HPT

Water Bypass Kits

FPE Coolant Bypass Kits...

LOW STOCK! Est Ship 3-5 days. HURRY! LOW STOCK. This item is in limited stock at one of our distribution centres. The ETA is the approximate time required to prepare your order for dispatch.

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Description

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.

Part Type

Engine Coolant Bypass Kit

Data: v4.2 - Upd: 2026-10-13 23:15:21

Features

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

Specifications

Product Attributes - Brand: Fleece Performance
Product Attributes - Manufacturer's Part Number: FPE-CLNTBYPS-CUMMINS-MAN
Product Attributes - Part Type: Water Bypass Kits
Product Attributes - Product Line: Fleece Performance Coolant Bypass Kits
Product Attributes - UPC: 635909310419
Product Attributes - Water Bypass Spacer Included: Yes
Product Attributes - Water Bypass Spacer Material: Billet aluminum
Product Attributes - Water Bypass Spacer Finish: Black anodized
Product Attributes - Water Bypass Hoses Included: Yes
Product Attributes - Water Bypass Hose Material: Braided stainless steel
Product Attributes - Fittings Included: Yes
Product Attributes - Fitting Material: Aluminum
Product Attributes - Fitting Color: Black
Product Attributes - Quantity: Sold as a kit.
Product Attributes - Notes: For use with manual transmission trucks only.

Reference Information

Brand Name/s	Fleece Performance
StreetFX SKU	fpexFPE-CLNTBYPS-CUM-9HPT
SFX Item ID	4228251
Supplier Item Code	4228251
Manufacturer SKU	FPE-CLNTBYPS-CUMMINS-MAN
Manufacturer UPC	635909310419
Alternative References	fle-s0106, 5.9L, 6.7L