Fleece FPE-CLNTBYPS-CUMMINS-1318 Cummins Coolant Bypass Kit | 2013-2018 RAM 2500/3500 6.7L Cummins

Features

• Adds a secondary thermostat-based coolant bypass system

• Reduces coolant temps at the rear cylinders

• Helps prevent freeze plug blowouts

• Improves cooling consistency across all six cylinders

• AN O-ring fittings for a leak-free seal

• Includes braided nylon hose with high-temp protective sleeve

• OE-style fit for seamless integration

Enhanced Cooling Where It Matters Most

The Fleece Performance Coolant Bypass Kit is engineered to solve a critical issue in the 6.7L Cummins engine—insufficient coolant flow to the rear cylinders. These cylinders experience the highest temperatures, increasing the risk of coolant pressure spikes and freeze plug failures. Fleece addresses this by adding a temperature-activated bypass system (not just pressure-based like other brands), allowing consistent coolant flow throughout the block. The result is lower rear-cylinder temps, better thermal balance, and improved long-term engine reliability.

Essential Upgrade for Durability

Whether you're towing, racing, or daily driving, this kit provides vital protection against over-pressure and hot spots that can lead to costly damage. The complete kit includes high-quality gaskets, AN O-ring fittings, braided lines, and front/rear thermostat housings for a reliable, leak-free install. It's one of the smartest upgrades to ensure your 6.7L Cummins engine remains strong and dependable under heavy loads and extreme conditions.

Fitment:
2013, 2014, 2015, 2016, 2017, 2018 RAM 2500 & 3500 6.7L Cummins

Warranty:
Manufacturer’s Limited Warranty

Fitment Notes:

• Compatible with factory and modified EGR systems

• Not designed for use with deleted trucks running no EGR crossover

• Recommended for high-performance, heavy-towing, or prolonged-idling applications