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SKU #: FPE-CLNTBYPS-CUMMINS-0607 MPN #: FPE-CLNTBYPS-CUMMINS-0607

Fleece Performance Coolant Bypass Kit 06-07 5.9L Auto Trans Cummins

$379.00
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Fleece Performance Coolant Bypass Kit for 06-07 5.9L Auto Trans Cummins
Description
Help eliminate the chance of scored rear cylinders and blown freeze plugs on your 5.9L Cummins with this Coolant Bypass Kit from Fleece Performance! The Fleece Coolant Bypass 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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Help eliminate the chance of scored rear cylinders and blown freeze plugs on your 5.9L Cummins with this Coolant Bypass Kit from Fleece Performance! The Fleece Coolant Bypass 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.
EXECUTIVE ORDER #D-834-9
Manuals and Guides
Vehicle Fitment
2006-2007 Dodge 5.9L Cummins Auto Transmission
WARNING: Cancer & Reproductive Harm - P65Warnings.ca.gov
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 black nylon 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: 4.1666665 / 5 from 6 reviews.

AI Generated Review Summary

Summary topics

Review topics: ["install","issues","kit","lines"].

Review highlights

Reviews

Bad luck with my kit

"My kit came with a stainless steel braided line, and it didn’t last a full year before it started leaking right where it’s held down by the rear bracket to the head. I expected this to be a long lasting kit that wouldn’t give me any problems, but rather solve the potential issue of blowing the rear freeze plug. Now I gotta order a $70 line and wait until I’ve got time to pull my transmission, since this line is near impossible to get to on the back side of the engine now that my engine is obviously back in the truck. I’m spending $40 per week on coolant at this point until i can get to it, but maybe it’s just bad luck, I doubt most kits would experience the same issue I did."

— Jacob (3/5)

The item was great and

"The item was great and showed up well packaged. Installation was challenging but that is not on anyone but me. I do have some temp fluctuations that don’t make a lot of sense. Lower temp on gauge but it seems to bounce from low temp to regular temp when between running on freeway to stop and go traffic. Not sure why or if it has to do with 180 temp thermostat with a 190 stock one."

— Nathan H. (3/5)

American made

"Not the easiest install, but fit and finish is top notch. Fleece is one of the best in the business."

— Daniel K. (5/5)

Braided for the eyes

"This product did lower my engine temps. a bit, but I feel secure that the coolingwater is spread out more evenly out to all cylinders equally. But damn, those black braided line looks stunning! Products from Fleece are ALWAYS top notch."

— Magnus L. (5/5)

Great Upgrade for Engine Coolant System

"Was a bit of a challenge to get to the back freeze plug against the firewall. Once that was done the rest of the system was easy to install. The upgrade kit does what it says it does. Truck runs around 10-15 degrees cooler now. Before stayed at 200 unless getting on it, now around 185 to 190. Worth it for sure!!! Added bonus is the AC seems to be running better now which is a weird extra."

— Joshua M. (4/5)

Awesome

"This. . . . this right here. . . . this thing here. . . this hose thingy with the valve thingy and that block plate thingy. . . . omg. . . Zeus himself installed this on his own chariot. . . IF YOU WANT INSTANT COOLING SYSTEM PERFORMANCE. . . . this is the way to go. Fit was perfect and function is perfect. Usually ran ~200-210 at all times. . . I can haul a full bed of wood or rocks now and my temps stay below 200. . . . regular cruising stays ~190. . . . THIS UPGRADE IS A MUST FOR COOLING SYSTEM PERFORMANCE. . . . thank you guys so much!!"

— Michael F. (5/5)

Q&A

I’ve looked up videos saying this product was originally meant for a drag/sled pull built diesel. Am I wasting money or will this still help my motor out even if my truck is bone stock for the most part. My truck is a project more of a toy rather than for work.
It will certainly help you out still. You are going to be eliminating coolant flow through the factory transmission heat exchanger so I woudl also recommend new transmission cooler lines to bypass that. -Sands
What is different between the auto trans and manual as far as install different steps or parts?
Different steps and parts. The Auto kit has provisions to bypass the heat exchange on the driver side of the engine. -Sands
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