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"I love this upgrade to my truck, install and serving the thermostat isn't easy in my opinion, but I'm still would not change buying it."
Cummins
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SKU #: FPE-CLNTBYPS-CUMMINS-0607-SS
MPN #: FPE-CLNTBYPS-CUMMINS-0607-SS
Fleece Performance Coolant Bypass Kit W/Stainless Braided lines 06-07 5.9L Auto Trans Cummins
Description
Help eliminate the possibility of scored rear cylinders and blown freeze plugs in your 5.9 Cummins with this Coolant Bypass Kit from Fleece Performance! The Fleece Coolant Bypass with Stainless Lines solves the problem of excessive coolant pressure before it becomes a problem. The integrated secondary thermostat locates at the back of the block and allows coolant to flow freely when at normal operating temperatures ensuring consistent temperatures across all six cylinders and eliminates excessive pressure. The kit comes with high quality AN o-ring fittings and AN hose connections with braided hose to ensure a leak free installation and installs in two hours or less!
Increased Coolant Flow, Decreased Coolant Temperatures - The rear cylinders on the 24 Valve 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. Fleece's 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.
Why do I need a Fleece Coolant Bypass? - One of the biggest issues on the 24 valves 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.
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FEATURES & BENEFITS:
- Lowers coolant temperature at the rear cylinders
- Ensures consistent temperatures across all cylinders
- Prevents damaging coolant pressure build up
- Complete kit comes with Stainless Steel braided hose and AN O-ring fittings to ensure a leak-free installation.
About Fleece Performance Engineering
Browse Fleece Performance Engineering Parts Online by Make, Model, and Year.
Fleece Performance Engineering is a customer-centric diesel performance company that specializes in the development and manufacturing of innovative and extremely forward-thinking products to improve upon the performance and reliability of your Cummins, Duramax, or Powerstroke. Originally operating from a shop on their family farm, they have now grown to a full-scale operation that excels in air and fuel-related components for light-duty diesel. A continuous focus on product quality and the creation of new design principles before the competition is what keeps Fleece Performance growing by leaps and bounds year after year and at the forefront of the winners circle. Many know Fleece for its line of Cheetah Turbos, PowerFlo Lift Pumps, and 10mm Stroker Pumps, but it goes far beyond! From the simple, yet widely popular exhaust manifold stud kits that eliminate the troublesome factory manifold hardware to full-blown race engines via their Freedom Racing Engines division, they are truly a "one-stop shop!" And no, Fleece isn't "just" for the hot rod diesel market, they've got kits and components for every level of diesel truck owner.
TIMELINE OF FLEECE PERFORMANCE ENGINEERING:- 2008: Fleece Performance Engineering was established in North Salem, IN by Brayden and Chase Fleece. Both had a passion for continuously innovating and improving upon products already on the market. Brayden's 2004.5 LLY Duramax became the test bed to develop the TurboBrake and Duramax Cheetah, while Chase's 2002 Cummins was one of the first Cummins pickups to integrate an Allison Transmission.
- 2012: Fleece Performance upgrades both facility and location by relocating to Nitro Alley in Brownsburg, IN situated among some of the top racing leaders in the world.
- 2014: Fleece Performance acquires the area's premier engine machine shop, Freedom Racing Engines. The acquisition enables Fleece Performance to expand the engine development program and product offerings. Today, Fleece Performance and Freedom Racing Engines build some of the most competitive engines in the industry.
- 2018: Fleece Performance breaks ground on a new 75,000 sq. ft. facililty in Pittsboro, IN.
- 2019: Fleece Performance and Freedom Racing Engines relocates to its new facility in Pittsboro, IN. The all new headquarters provides additional space for product development, production and work areas, assembly and testing, a larger warehouse, as well as four engine dynamometers, and two-story office space.
- 2020: Fleece Performance receives ISO9001:2015 Certification.
- 2021: Fleece Performance Engineering was voted as one of the Best Places to Work in Indiana by the Indiana Chamber of Commerce.
- 2022: Fleece Performance Engineering was voted again as one of the Best Places to Work in Indiana by the Indiana Chamber of Commerce.
As always, if you have any questions about which Fleece turbo, fuel, engine, or other product is right for you, do not hesitate to give us a call and we would be happy to assist.
Video
Product Overview: Fleece Coolant Bypass Kit 94-22 Dodge 5.9L / 6.7L Cummins
Keeping coolant temperatures under control can be a real chore on an inline 6 with a turbo producing lots of heat and rear cylinders being under a cowl. Fleece Performance Engineering has your 5.9L / 6.7L Ram Cummins covered from 1994-2022! Help your 2nd, 3rd, 4th, or 5th generation truck stay cool while working hard.
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Overall rating: 5.0 / 5 from 6 reviews.
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Review highlights
Reviews
Quality
"Fleece builds quality! The install was a good project with both engine and trans in place. A little effort and a good review of every you-tube video available led to another excellent upgrade. . My complements to Diesel Power Products and Fleece"
Lowered Coolant temps
"Fleece products are always awesome, the QA QC is spectacular. I was shocked of the quality in the aluminum and the length and fit of the stainless braided coolant hose. I was replacing my engine I my 2006, and decided to do the coolant bypass. Yes, it was much easier to install with the engine out of the truck."
Great product
"Great product"
Component of the gods
"This thing here. . . right here. . . with the floppy hose thingy and the block plate with the valve thingy. . . Zeus himself installed it on all his own Cummins powered chariots. . . WHAT A HUGE PERFORMANCE DIFFERENCE FOR THE COOLING SYSTEM. ~running temps were always above 200 for me, after this and a new main thermostat. . . I can haul a whole bed load of wood or rocks and I still stay cooler than before. Regular cruising never goes above 190’. Thank you so much for this product."
Must have!
"I'm very happy with this. I waited until I was doing a transmission swap to install this and I'm glad I did! I wouldn't attempt this with the transmission in. I also purchased a mishimoto 180 degree thermostat for the main thermostat housing and my pickup stays cool no matter what I'm using her for. The stainless braided hose is a little long but I hid the extra slack behind the engine. Worth every penny, a must have in my opinion."
Q&A
- Does it include the thermostat for the rear?
- Yes, the coolant bypass block that bolts to the freeze plug hole on the back of the cylinder head, does contain a thermostat.