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Mishimoto

Mishimoto 03-07 Dodge Ram 5.9L Cummins Replacement Transmission Cooler

4.7 store rating · 572 reviews
SKU: MISMMTC-RAM-03TQ

Fits 2003–2007 Dodge Ram 2500 / 3500 · 5.9L Cummins

All 11 applications
$168.99
Only 3 left. Ships in 1–2 business days.
25200 Entries150X
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  • Authorized dealerGenuine Mishimoto parts, sourced direct
  • 30-day returnsSee the return policy
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The factory transmission oil cooler on your 2003-2007 Dodge Ram 5.9L Cummins is a liquid-to-liquid cooling unit, utilizing the engine's cooling system to cool the transmission fluid during warm outside temperatures and warm the fluid during cold outside temperatures. This design is tried and true, and it works. Until it doesn't. When they wear out and fail, it can leak coolant into your transmission fluid. Mixing coolant into your transmission fluid can have catastrophic results, and nobody wants to spend thousands of dollars to rebuild or replace their transmission if it can be avoided. The Mishimoto Replacement Transmission Oil Cooler is a direct fit, OEM replacement that requires no modification to install. Made to OEM specifications, this transmission oil cooler is equivalent to an OEM part. By replacing your transmission cooler preventatively, you can save your transmission from falling victim to premature failure. As with all of our products, this cooler is backed by our signature Mishimoto Lifetime Warranty.

Installation Instructions
  • Includes new powdercoated bracket and brass fittings for easy installation
  • Equivalent to OEM specifications for fit and function
  • Durable, corrosion-resistant aluminum construction

Reviews

What customers say

Verified reviews collected by Loox from real orders.

Good to know

Questions, answered straight.

If it is not here, call or text the counter. Real people, real answers.

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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Why buy here

A diesel shop that sells parts, not a website that sells boxes.

Every part on this site is one our own techs can stand behind.

  • We run what we sell

    A working diesel repair and fabrication shop in Nazareth, PA. These are the parts our techs install every week.

  • Real techs on the phone

    Call or text 908-223-9744 and you get a diesel tech, not a script.

  • Authorized dealer

    Genuine parts straight from the manufacturer, with the factory warranty behind them.

  • Fast from stock

    Most in-stock parts ship in 1 to 2 business days from warehouses across the USA.

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Full Send Diesel, Nazareth, PA

A team of diesel people, not a call center.

Full Send Diesel is a shop full of techs, builders and parts people in Nazareth, Pennsylvania. When you call or text, you reach someone who works on these trucks and knows the parts.

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.

Call 908-223-9744 Text us Email

Mon–Fri, 8am–4pm ET. After hours, text or email and we answer first thing in the morning.

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