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SKU #: MISH-MMTS-RAM-89L MPN #: MMTS-RAM-89L

Mishimoto Low Temperature Coolant Thermostat 89-93 Ram 5.9L Cummins

$64.95
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Description
Keep your diesel running cooler and more consistent with the Mishimoto Low-Temperature Thermostat. Designed to activate at a lower temperature than the factory unit, this thermostat allows coolant to begin circulating through the radiator sooner. Earlier coolant flow helps manage heat more effectively, especially when the engine is working hard! Lower operating temperatures can make a noticeable difference during towing, heavy loads, or long drives in warmer climates. By helping regulate heat earlier in the cooling cycle, this thermostat supports stable engine temperatures and reduces stress on critical components. For Cummins owners who rely on their truck for demanding work or daily driving, improved temperature control can add confidence behind the wheel. Built with quality materials and engineered for dependable performance, this thermostat is a simple upgrade that can make a real impact on cooling efficiency. The included gasket helps ensure a proper seal during installation, making it an easy way to refresh the cooling system and keep your engine performing at its best.

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Keep your diesel running cooler and more consistent with the Mishimoto Low-Temperature Thermostat. Designed to activate at a lower temperature than the factory unit, this thermostat allows coolant to begin circulating through the radiator sooner. Earlier coolant flow helps manage heat more effectively, especially when the engine is working hard!

Lower operating temperatures can make a noticeable difference during towing, heavy loads, or long drives in warmer climates. By helping regulate heat earlier in the cooling cycle, this thermostat supports stable engine temperatures and reduces stress on critical components. For Cummins owners who rely on their truck for demanding work or daily driving, improved temperature control can add confidence behind the wheel.

Built with quality materials and engineered for dependable performance, this thermostat is a simple upgrade that can make a real impact on cooling efficiency. The included gasket helps ensure a proper seal during installation, making it an easy way to refresh the cooling system and keep your engine performing at its best.

Vehicle Fitment
1989-1993 Dodge/Ram 5.9L Cummins
WARNING: Cancer & Reproductive Harm - P65Warnings.ca.gov
FEATURES & BENEFITS:
  • Direct-Fit Replacement: Designed specifically for 1989–1993 Dodge Ram trucks with the 5.9L 12-valve Cummins for straightforward installation.
  • Lower Activation Temperature: Opens at 174.2°F to allow coolant to circulate earlier and help maintain cooler engine temperatures.
  • Improved Cooling Control: Helps reduce heat buildup during heavy towing, hard driving, or high-temperature environments.
  • Ideal for Warm Climates: Supports better temperature management in hot weather and demanding conditions.
  • Complete Installation Kit: Includes thermostat and high-quality gasket for a proper seal during installation.

SPECIFICATIONS:
  • Applications: Dodge D250 I6 (5.9L) 1989-1993; Dodge D350 I6 (5.9L) 1989-1993; Dodge W250 I6 (5.9L) 1989-1993; Dodge W350 I6 (5.9L) 1989-1993
  • Engine Codes: 6BT
  • Chassis Codes: D/W Series
  • Mishimoto Activation Temperature (F): 174.2
  • OEM Activation Temperature (F): 180
  • Purchase Includes: (1) Mishimoto Thermostat; (1) Thermostat Gasket
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.