FLEECE FPE-CLNTBYPS-CUMMINS-VP VP COOLANT BYPASS KIT 1998.5-2002

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 and up 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.

Enhance the performance and longevity of your 5.9/6.7L Cummins engine with the FLEECE FPE-CLNTBYPS-CUMMINS-VP VP Coolant Bypass Kit, designed specifically for models from 1998.5 to 2002. This innovative kit significantly increases coolant flow, effectively lowering temperatures for the rear cylinders that are prone to overheating.

Overheating can lead to extreme pressure within your cooling system, causing critical components like freeze plugs to fail. The Fleece Coolant Bypass Kit addresses this issue head-on by introducing a secondary thermostat. Unlike conventional systems that react to pressure build-up, our solution operates based on temperature, maintaining optimal conditions across all six cylinders, thereby preventing catastrophic failures.

• Lowers coolant temperature at the rear cylinders to prevent overheating
• Ensures consistent temperatures across all cylinders for improved reliability
• Prevents damaging coolant pressure buildup and potential failures
• Complete kit includes braided hose and AN O-ring fittings for a leak-free installation
• Kits for MY 2003 and up incorporate billet hose brackets for enhanced durability

The Fleece Coolant Bypass Kit is essential for ensuring the health of your Cummins engine. If you're serious about performance and reliability, this kit is a critical upgrade that every Cummins owner should consider. Don’t let coolant flow issues lead to expensive repairs—make the smart choice today.