SKU: 40351058994

Fleece Performance Coolant Bypass Kit 03-07 5.9L Manual Trans Cummins

Sale price$170.55 Regular price$189.50
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Description

Fleece Performance Coolant Bypass Kit 03-07 5.9L Manual Trans CumminsHelp eliminate the possibility of scored rear cylinders and blown freeze plugs on your 5. 9 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

Help eliminate the possibility of scored rear cylinders and blown freeze plugs on your 5.9 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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SKU: 40351058994

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Brennan White
Battle Creek, US
★★★★★ 5
Good quality, great for the beach
This is great for ocean and beach fetch! The spikes keep the sand and saltwater from getting in my pups mouth and upsetting her stomach. It also floats well and doesnt fill with water. I have had this for about a month now and in surprisingly good shape considering how obsessed with it my dog is. Not gonna lie, I avoid squeakers since my dog is an absolute menace with them but i assumed the squeaker would break almost immediately, however it is still going strong much to my annoyance🤣
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Reviewed in the United States on March 16, 2026
B
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Becky L
West Palm Beach, US
★★★★★ 5
Great Product!
Size: 5.75 inch (Pack of 1)
My dog is a chewer! She can chew through most chew toys in a day. This has been a lifesaver! She chews on it but has not been able to get any pieces off of it. It is Durable and she loves it! This is a great item. I intend to buy more like this. It is a great product!
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Reviewed in the United States on June 3, 2026
A
Verified Purchase
Alianna
Bozeman, US
★★★★★ 5
Amazing toy for large dog breeds!
Size: 9.5 inch (Pack of 1), Size: 9.5 inch (Pack of 1)
My puppy Rottweiler loves this toy! Withstands her heavy chewing and really seems to soothe her! It’s very loud against the floor. She struggled a bit at first with picking it up but now it’s no problem. Highly recommend for big dogs
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Reviewed in the United States on January 14, 2026
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Verified Purchase
K.D.
Carnegie, US
★★★★★ 5
My puppy's favorite stick, high quality
Size: 5.75 inch (Pack of 1)
Perfect quality chew toy for my dachshund puppy. She will spend several minutes everyday chewing on this. It is the perfect size for her small mouth and it doesn't show signs of wear like most sticks do.
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Reviewed in the United States on May 31, 2026
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Stephanie
Omaha, US
★★★★★ 4
Durable
Size: 5.75 inch (Pack of 1), Size: 5.75 inch (Pack of 1)
Great buy would highly suggest for dogs that love to chew. I bout a large one for our 5 year old Husky and a medium one for our 11 week old puppy. Both are very intrigued by them and the puppy loves playing fetch with it. The only complaint I have is the size difference between the large and the small. I know measurements were given but the medium looks more like a very small stick. If you have a larger go with the Large size. Medium would really only work for smaller size dogs and pups
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Reviewed in the United States on March 1, 2024

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