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SKU #: MISH-MMTC-RAM-03SL MPN #: MMTC-RAM-03SL

Mishimoto Transmission Cooler 03-09 Ram 5.9L / 6.7L Cummins

$599.95
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Description
Your Cummins powered Ram is a beast, and you don’t want to kill it’s transmission by letting heat cause premature transmission failure. Whether your Dodge Ram 5.9L/6.7L Cummins is a dedicated tow vehicle, hardworking fleet truck, or a daily driver with a liking for the drag-strip, you need to ensure that your transmission runs cool. Luckily, Mishimoto has developed a direct-fit transmission cooler to do just that. The 2003-2009 Dodge Ram 5.9L/6.7L Cummins transmission cooler utilizes a stacked plate core for durable and powerful cooling. With a massive 212% greater core volume and 244% increase in fluid capacity, this trans cooler is a huge improvement over stock Dodge Ram 5.9L / 6.7L Cummins transmission cooler. The Mishimoto transmission cooler is not only larger than the stock cooler, but more reliable too. When the stock cooler’s thermostat fails, it fails closed, bypassing the cooler and returning hot fluid to the transmission. Mishimoto has solved this common issue by making the thermostat in our 2003–2009 Dodge Ram with a 5.9L or 6.7L Cummins transmission cooler fully serviceable and easily bypassed for constant cooling. A port located at the top of the cooler provides easy access to the thermostat for servicing in just a few minutes. Replacement thermostats can be purchased individually if needed; no more replacing the entire cooler if the thermostat fails. Owners in cold climates can still enjoy the fast warmup times that the thermostat provides, while owners in hot climates can choose to bypass the thermostat by replacing it with the supplied stainless-steel bypass plug. To make this cooler even easier to install and service, Mishimoto saves you the hassle of removing seized fittings. The provided CNC-machined, stainless steel hose barb fittings let you cut to the chase, literally. These fittings and the supplied transmission cooler hose allow you to remove the quick-disconnect fittings and connect the stock soft-line to the Mishimoto cooler. Like all Mishimoto products, this transmission cooler is backed up by Mishimoto’s Lifetime Warranty with Accident Protection for worry free cooling as long as you own it.

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Your Cummins powered Ram is a beast, and you don’t want to kill it’s transmission by letting heat cause premature transmission failure. Whether your Dodge Ram 5.9L/6.7L Cummins is a dedicated tow vehicle, hardworking fleet truck, or a daily driver with a liking for the drag-strip, you need to ensure that your transmission runs cool. Luckily, Mishimoto has developed a direct-fit transmission cooler to do just that. The 2003-2009 Dodge Ram 5.9L/6.7L Cummins transmission cooler utilizes a stacked plate core for durable and powerful cooling. With a massive 212% greater core volume and 244% increase in fluid capacity, this trans cooler is a huge improvement over stock Dodge Ram 5.9L / 6.7L Cummins transmission cooler.

The Mishimoto transmission cooler is not only larger than the stock cooler, but more reliable too. When the stock cooler’s thermostat fails, it fails closed, bypassing the cooler and returning hot fluid to the transmission. Mishimoto has solved this common issue by making the thermostat in our 2003–2009 Dodge Ram with a 5.9L or 6.7L Cummins transmission cooler fully serviceable and easily bypassed for constant cooling. A port located at the top of the cooler provides easy access to the thermostat for servicing in just a few minutes. Replacement thermostats can be purchased individually if needed; no more replacing the entire cooler if the thermostat fails. Owners in cold climates can still enjoy the fast warmup times that the thermostat provides, while owners in hot climates can choose to bypass the thermostat by replacing it with the supplied stainless-steel bypass plug.

To make this cooler even easier to install and service, Mishimoto saves you the hassle of removing seized fittings. The provided CNC-machined, stainless steel hose barb fittings let you cut to the chase, literally. These fittings and the supplied transmission cooler hose allow you to remove the quick-disconnect fittings and connect the stock soft-line to the Mishimoto cooler.

Like all Mishimoto products, this transmission cooler is backed up by Mishimoto’s Lifetime Warranty with Accident Protection for worry free cooling as long as you own it.

Vehicle Fitment
2003-2009 Dodge 5.9L / 6.7L Cummins
WARNING: Cancer & Reproductive Harm - P65Warnings.ca.gov
FEATURES & BENEFITS:
  • Fits all 2003–2009 Dodge Ram 5.9L & 6.7L Cummins
  • 212% Increase in core volume
  • 244% Increase in fluid capacity
  • Includes fully serviceable thermostat for fast warm-up in cold climates and thermostat bypass for constant cooling in hot climates
  • Stacked-plate design for tough and reliable cooling
  • Eliminates corrosion-prone quick-disconnect fittings
IMPORTANT NOTE:

This kit requires cutting of the stock transmission cooler lines to remove the quick-disconnect fittings. Mishimoto provides CNC-machined stainless steel hose barb fittings to splice the supplied transmission cooler line with the stock soft-lines.

About Mishimoto
MISHIMOTO PERFORMANCE PARTS ONLINE

Mishimoto Automotive Performance is a leader in aftermarket cooling components. Mishimoto offers car and race enthusiasts of all levels and interests quality upgrades, from aluminum radiators to racing thermostats, which will significantly enhance engine performance. Whether you’re a daily driver behind the wheel of a diesel or gasoline truck, a track racer in a sport compact vehicle, or a motocross rider, you can trust Mishimoto products to hold up in any condition you might encounter. The research and development group at Mishimoto is a team of devoted automotive professionals who naturally anticipate the needs of drivers looking for quality cooling system upgrades. Mishimoto truck radiators are made from high-quality aluminum for dependable performance you can count on time and again.

MISHIMOTO PRODUCTS

From design to manufacturing, every Mishimoto component is carefully crafted to be the ultimate cooling system upgrade. All Mishimoto aluminum radiators are application specific, designed for direct fit on numerous popular car models and makes. Mishimoto aluminum racing radiators are designed to provide your engine with a more efficient transfer of heat over stock models, thus enhancing overall engine performance. Mishimoto dirt bike radiators are made with the same 100% brazed aluminum used in the sport compact and truck models. Mishimoto dirt bike radiator hoses are constructed of four hand-wrapped layers designed to withstand intense racing conditions. Every layer combines high-grade silicone and heat-resistant embedded fibers to withstand amplified pressure and effectively reduce heat. Mishimoto front mount intercoolers come in a range of sizes to offer the ideal air intake for any turbocharged or supercharged engine. Mishimoto offers a full catalog of cooling components, from aluminum fan shrouds to racing thermostats, all precision crafted to deliver the highest level of racing performance.

MISHIMOTO RADIATORS

The radiator on your truck plays a critical role in keeping engine temperatures at bay. Not only does it store coolant, the design of the core ensures that as air passes through the tubes, the coolant can experience a temperature drop before being recirculated back into the engine where it will be reheated again. Overtime, the core of the stock radiator will become damaged from bugs, your foot as you stand on the front bumper, or just about anything else that can damage the fins, in turn causing a loss in cooling efficiency. That said, even in new condition, the core is not designed with maximum cooling in mind. Mishimoto designs and manufacturers premium aluminum radiators that not only look exceptional, but provide additional cooling that a stock radiator simply can’t match.

MISHIMOTO INTERCOOLERS

Just as with radiators, your intercooler has a very important job to do. As air is forced into the compressor side of your turbo(s), it then passes through tubing and into your intercooler where ambient air passing through the intercooler cools the air, in turn “charging” it to superspeed it into your engine cylinders. As damage and dirt accrue, the stock intercooler can no longer adequately cool this air, resulting in a loss of boost pressure and an increase in exhaust gas temperatures (EGT). While many will fight their tuning or begin changing out injectors and turbo, many times it’s a matter of merely upgrading the intercooler. Mishimoto designs and manufactures high performance aluminum intercoolers that work just as well on performance built engines as they do on a completely stock powertrain.

MISHIMOTO CATCH CANS

Does your driveway or garage floor have oil spots? Its likely your engine has a crankcase vent. Some trucks recycle your crankcase oil back into the engine where others either have an open ended hose or a stock catch can that is open on the top, both of the latter allowing oil to land wherever gravity dictates. Mishimoto’s line of premium catch cans are designed with serviceability and cleanliness in mind. These are universal aluminum cans that allow you to route your existing hose (typically with added length) to an easily accessible area to catch all of that sludge. This allows you to dump it at will instead of constantly dripping on your undercarriage and driveway.

MISHIMOTO LIFETIME WARRANTY

Customer satisfaction has been the foundation of the Mishimoto philosophy since its inception. Mishimoto is a name customers can trust to provide a lifetime of performance satisfaction with every aluminum radiator and cooling component. To back this promise, Mishimoto extends a “no questions asked” limited lifetime warranty that covers every product in the Mishimoto catalog. Mishimoto will gladly replace an original product should customers experience a defect or issue. To avoid any unnecessary issues, Mishimoto encourages customers to have professionals handle product installation. Any concerns relating to installation or compatibility should be addressed before installing any product.

ACCIDENT PROTECTION

The Mishimoto lifetime warranty policy also provides for accident protection for Mishimoto components damaged during an accident. Accident protection warranties will be honored for customers who submit a warranty claim with pictures of the accident and an official police report within three months of the incident.

Overall rating: 4.965517 / 5 from 29 reviews.

AI Generated Review Summary

The Mishimoto Transmission Cooler for 2003-2009 Dodge Ram 5.9L/6.7L Cummins offers a reliable and powerful cooling solution with a larger core volume and fluid capacity than the stock cooler. It features a serviceable thermostat and easy installation, though opinions on its cooling effectiveness vary.

Summary topics

  • Cooling Effectiveness: 23%
  • Product Fit: 32%
  • Ease of Installation: 23%

Review topics: ["fit","instructions","quality","install","shipping","cooler","temps"].

Review highlights

  • "High quality, perfect fit."JAMES O.
  • "It fit perfect very straight foward install over all very happy with the fit and finish quality product!"Donald P.
  • "This cooler is a great fit."Brian

Reviews

"Very nice transmission cooler. Would recommend. Dropped temps 40-50 degrees when paired with deep sump transmission pan with heat exchanger bypass."

Blakely (5/5)

Trans Cooler

"Finally purchased the Mishimoto transmission cooler, another puzzle piece to making my 5. 9 Cummins rock solid. Shipping was fast. I unboxed it and the cooler looked great except a few fins were smashed down (most likely from the hardware pack in the box not being secured). Overall a good deal for a quality cooler that should last a long time."

Clinton W. (5/5)

"Took my transmission temps from constantly above 180 to never seeing over 150"

Roman (5/5)

Perfect fit

"This cooler fit perfect with no modifications and help me keep the warranty on my new Randy’s trans , I definitely can tell the difference in staying cooler and the time it takes too cool down when warm! Would highly suggest getting the upgraded trans lines with it"

Georgia F. (5/5)

This thing is peace of mind in a box

"05 Cummins with 48re. Was averaging trans temp around 190 and occasionally 220 F uphill, UNLOADED. Having just rebuilt my 48 I knew I needed to do something. Now running 160 - 175 on all grades and with load. Easy install and gives you an excuse to clean up your other coolers. Make sure to have an extra couple quarts of ATF+4. It is bigger. Worth every penny."

Tobias A. (5/5)

10/10

"Fits perfectly and keeps my trans under 160 all summer long"

Georgia F. (5/5)

Great product

"The cooler and everything works really well even keeps a good temp in lock up which I like cause before it would dump temp fast even towing in the summer time. The only complaints I have is the way the lines hook up I’m kinda afraid that they’ll blow off and spray all my trans fluid out. I think it should come with a line kit. The clamps were terrible also I had to buy a few new ones cause I broke them and some of the lines I couldn’t get as tight as I wanted they actually spin around on the fittings that’s why I broke the clamps in the first place."

David E. (5/5)

Mishimoto trans cooler

"Completely put my mind at rest. Trans doesn’t get hotter than 160-175, before it would hit 215 or slightly more in traffic!"

Jonathan D. (5/5)

Fits exactly how it should.

"Fits exactly how it should. Keeps the oil temperature in check"

Brenden M. (5/5)

Perfect fit

"Couldn’t ask for a better fit and finish. My transmission is running way cooler. Averaging 130° with ambient air temp around 85°."

Thomas B. (5/5)

Q&A