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Mishimoto MMTS-RAM-99L Low Temperature Racing Thermostat, Compatible with Dodge Cummins 5.9L & 6.7L, 1999-2013

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$74.95

$ 32 .99 $32.99

In Stock

About this item

  • Direct fit for 1999-2013 Dodge Ram with 5.9L/6.7L Cummins
  • Lower activation temp allows coolant to flow through the engine earlier
  • Ideal for vehicles in warm climates or under extreme towing/driving conditions
  • Mishimoto Activation: 180F (82C) / OEM Activation: 190F (87.5C)
  • Mishimoto Lifetime Warranty


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 Low-Temperature Thermostat! This thermostat is designed as a direct-fit replacement for your aged factory unit. The Mishimoto thermostat has a lower activation temperature (180 degrees Fahrenheit) compared to the factory thermostat (190 degrees Fahrenheit for 99-10 and 2013 trucks & 200 degrees Fahrenheit for 10-12 trucks). The lower activation temperature allows coolant to flow through the engine earlier, which reduces and maintains lower engine temperatures. This thermostat is ideal for use in warmer climates or under extreme towing/driving conditions. As with all our products, this thermostat includes the Mishimoto Lifetime Warranty, ensuring superior product quality and craftsmanship.


Patrick Martinez
Reviewed in the United States on September 30, 2024
Had this in my recently new motor. 5.9 cummins. Thought it would help with cooling. In the beginning it made about a 10 to 15 degrees difference. I thought this is great then about 3 months the truck started to run slightly hot. Checked everything and then came across this. All parts clip backing and retainer have yet to be found. If you buy this buyer beware. Diesel engines are not cheap.
G. M.
Reviewed in the United States on June 5, 2024
It's been in for a while now and is doing good. I had two stock ones fail withing a week. This one has been on two 20 hr trips now.
Max Malyuk
Reviewed in the United States on December 31, 2024
Thermostat decided to self destruct due to poor and weak design
Dennis Timmons
Reviewed in the United States on August 16, 2023
I have an 05 cummins 3500 put a brand new stant 180 thermostat in an fought an overheating issue, replaced rad to mishimoto and did fan clutch and water pump same issues, went to the mishimoto thermostat and cured my issue runs 175-183 in 86* outside, only time will tell about longevity, happy so far
Gregory Piet
Reviewed in the United States on August 16, 2020
The mishimoto radiators are top shelf but the thermostat has proven to be a let down.I put one of these thermostats in place when I did a mishimoto radiator on a Cummings diesel. It ran super cool for a few days and then it seemed to open up later and later. It settled opening around 205 to 210 and kept the vehicle temp around 205 and obviously higher when towing. I ran it for a couple months. I wasn't happy with it being a 180 stat and Temps climbing so much before I saw it open up. I tossed in an equivalent Stant and it opens up sooner, and runs about 5 degrees cooler at 80mph and about 15 cooler at 65mph. I'll keep the mishimoto radiator and transmission cooler but the thermostat is a hard pass.
Customer
Reviewed in the United States on August 21, 2019
Easy to install
Jodie Kinney
Reviewed in the United States on July 2, 2019
the truck has not been over 170 and its 90 outside best 62 dollars i ever spent
reelumn
Reviewed in the United States on November 26, 2016
I opens up around 178 and help keep my truck cooler. My fuel mileage went down and I ask dodge about it and under 190 the truck stays in cold mode and is giving a extra phase to the injectors.
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