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Fleece Performance

Fleece Performance 04.5-07 Dodge 5.9L Cummins Coolant Bypass Kit (06-07 Auto Trans)

4.7 store rating · 579 reviews
SKU: FPEFPE-CLNTBYPS-CUMMINS-0607

Fits 2006–2007 Dodge Ram 2500 / 3500 · 5.9L Cummins

All 10 applications
$425.99
Only 2 left. Ships in 1–2 business days.
  • Authorized dealerGenuine Fleece Performance parts, sourced direct
  • 30-day returnsSee the return policy
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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+ 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.

Installation Instructions
Installation Instructions
Warranty
  • Complete kit comes with braided hose and AN O-ring fittings to ensure a leak-free installation
  • Ensures consistent temperatures across all cylinders
  • Lowers coolant temperature at the rear cylinders
  • Prevents damaging coolant pressure build up

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Fitment

  • Will this fit my truck?

    The Fits section at the top of the page lists the manufacturer's applications for this exact part. If your year, make and model is not there, or you are not sure, text us a photo of what you are replacing with your year and engine and we will confirm it before you order.

  • What if I order the wrong part?

    Call or text us before it ships and we will swap it. After delivery you have 30 days to return it in new, uninstalled condition. The return policy has the restocking details.

Shipping

  • When will it ship?

    In-stock parts usually ship within 1 to 2 business days from warehouses across the USA. The stock line under the options tells you the status of the part you are looking at. Large items ship LTL freight and we call to schedule delivery.

  • Why did I only get part of my order?

    We ship from multiple warehouses, so an order with several items can arrive in more than one box. Tracking for each shipment is emailed as it goes out. Full details in the shipping policy.

Returns and warranty

  • What is the return policy?

    30 days from delivery, in new and uninstalled condition, with a restocking fee. Everything is spelled out in the Returns & Refund Policy.

  • How do warranty claims work?

    We are an authorized dealer, so the manufacturer's warranty applies to every part we sell. Call or text us with your order number and we handle the claim with the brand for you.

Paying

  • Can I pay over time?

    Yes. Shop Pay installments are offered at checkout on qualifying orders, and the monthly estimate shows right under the price.

  • What is a core deposit?

    Some remanufactured parts, like injectors and turbos, carry a refundable core deposit. It is shown on the product page when it applies and refunded when your old part comes back to us.

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Not sure what you need? Send a photo of what you are replacing with your year and engine. We will point you to the right part, confirm it is in stock, and get it moving.

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