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SKU #: MISH-MMTS-RAM-99H MPN #: MMTS-RAM-99H

Mishimoto High-Temperature Thermostat 99-13 Dodge 5.9L / 6.7L Cummins

$83.95
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Description
A defective thermostat can result in engine overheating and potential internal damage. Improve the reliability of your 5.9L/6.7L cooling system with a Mishimoto Dodge 5.9L/6.7L Cummins High-Temperature Thermostat! This thermostat is designed as a direct-fit replacement for your aged factory unit. The Mishimoto thermostat has a higher activation temperature (205‚°F) compared to the factory thermostat (190‚°F for 9910 and 2013 trucks 200‚°F for 10-12 trucks). The higher activation temperature restricts coolant flow longer to allow a quicker engine warm-up, making this thermostat ideal for use in cold climates. As with all our products, this thermostat includes the Mishimoto Lifetime Warranty, ensuring superior product quality and craftsmanship. Mishimoto Activation Temperature: 205 Degrees Fahrenheit Factory Activation Temperature: 190 Degrees Fahrenheit (1999-2009 2013 Cummins) 200 Degrees Fahrenheit (2010-2012 Cummins)

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A defective thermostat can result in engine overheating and potential internal damage. Improve the reliability of your 5.9L/6.7L cooling system with a Mishimoto Dodge 5.9L/6.7L Cummins High-Temperature Thermostat! This thermostat is designed as a direct-fit replacement for your aged factory unit. The Mishimoto thermostat has a higher activation temperature (205‚°F) compared to the factory thermostat (190‚°F for 9910 and 2013 trucks 200‚°F for 10-12 trucks). The higher activation temperature restricts coolant flow longer to allow a quicker engine warm-up, making this thermostat ideal for use in cold climates. As with all our products, this thermostat includes the Mishimoto Lifetime Warranty, ensuring superior product quality and craftsmanship.

Mishimoto Activation Temperature:
  • 205 Degrees Fahrenheit

Factory Activation Temperature:
  • 190 Degrees Fahrenheit (1999-2009 2013 Cummins)
  • 200 Degrees Fahrenheit (2010-2012 Cummins)
Vehicle Fitment
1999-2013 Dodge 5.9L / 6.7L Cummins
WARNING: Cancer & Reproductive Harm - P65Warnings.ca.gov
FEATURES and BENEFITS:
  • Direct fit for 19992013 Dodge Ram with 5.9L/6.7L Cummins
  • Restricts coolant system circulation for longer time to provide quicker warm up
  • Ideal for cool climates
  • Mishimoto Lifetime Warranty
Kit Includes:
  • Mishimoto Thermostat
  • O-Ring
  • Mishimoto Lifetime Warranty
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: 4.0 / 5 from 10 reviews.

AI Generated Review Summary

Summary topics

Review topics: ["temps","thermostat"].

Review highlights

Reviews

Jonk

"Jonk install. It never got the right temperature. Drove it. 300 miles. Take it apart. Thermostat fall apart."

Ruben S. (1/5)

Temp

"Cold bubba"

Brett T. (5/5)

junk

"your company was good to work with but the product was junk the best temp I could get was 145 put old one back in"

Jeffrey K. (1/5)

Mislabeled Box

"I received the thermostat, in a box labeled as a high temp. I threw it in my truck, excited to keep the truck warm in colder weather. My ECT wouldn't break 180°, and was running low 170°s on my 40 minute drive to work. I pulled the thermostat, it was stamped 82°C, meaning it was the low temp thermostat. It took two weeks to get it sorted out, and Mishimoto sent me the correct thermostat. The replacement functions as it should, but apparently Mishimoto mislabeling boxes is such a big problem, it has its own dedicated box when you go to contact them. Their products work well, but you are essentially rolling the dice that you'll get the correct product when you order Mishimoto (They also sent me a 6. 4L Powerstroke overflow resevoir for my 5. 9L Cummins). Not any fault on Diesel Power Products."

Kam W. (3/5)

Failed after 6 months

"Purchased last year worked fine for about 4 months stuck open no heat live tech support said I had to deal with misomoto for warranty return. And well after reading all the bs associated with a return So no wouldn't recommend this product went to Cummins spent 40 bucks back up and running so zero stars on this product for me"

Stuart J. (5/5)

Like what I see. .

"Looking forward to seeing how this new thermostat performs but so far, I like it. From the moment I took it out of the box and saw the quality I was sold. If it works as good as it looks, I'll defiantly be back. Truck definatly warms up more quickly with this thermostat."

Chanel G. (5/5)

Very Satisfied.

"The Cummins stat opens for too long of periods and I see the temperatures drop to 178 in cold weather (-10f) when using a 190 t stat. With the Mishimoto the temperatures stay more steady. 188-190 while driving and pretty steady at 187-190 if stuck in traffic and ter the truck has warmed up. Just wish I guy could buy a 195 stat for these trucks."

Jessica G. (5/5)

Exactly what I was looking for

"I work the oil patch in North Dakota I've seen extreme cold spells shut Diesel's down for weeks -72 at the worst but this so far coming into winter -14 i haven't had to wrestler the bra on and off the old cummins yet keeps the motor hot, already know will have to be strictly a seasonal install"

Britni B. (5/5)

Great product

"Great product. Installs easy and works great. My diesel warms up much faster in cold temperatures"

Kacey I. (5/5)

You can tell this is a high quality thermosta. . .

"You can tell this is a high quality thermostat right out of the box. My old thermostat was stuck open causing extended warm up times. Replaced it with this one and all is good. With this thermostat operating temperature fluctuates between 195 and 205."

Delaney J. (5/5)

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