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Mishimoto

Mishimoto 89-93 Dodge 5.9L Cummins 79C High-Temperature Thermostat

$71.00 $64.95 Save $6.05

SKU: M00C MMTS-RAM-89L

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INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

Part #: MMTS-RAM-89L

The 12-valve first-gen Cummins in your Ram is considered one of the best diesel engines ever produced, and for good reason. Fuel efficiency, torque, and simplicity are just a few characteristics that give the Cummins its stellar reputation. We're huge fans of the Cummins engine, which is why we've developed a low-temperature thermostat for the 1989-1993 5.9L 12v Cummins. This Mishimoto thermostat activates at a lower temperature (174.2 degreesF) compared to the factory thermostat (180 degreesF). By lowering the activation temperature, coolant flows through the radiator earlier, maintaining lower fluid temperatures. The Mishimoto low-temperature thermostat is ideal for vehicles in warmer climates, or for use in vehicles experiencing extreme driving/towing conditions. This thermostat includes a high-quality replacement gasket and our signature Mishimoto Lifetime Warranty.

Low-Temperature Thermostat, fits Dodge 5.9L First-Gen Cummins 1989-1993

MIA's Description

The Mishimoto MMTS-RAM-89L is a low-temperature thermostat designed for improved cooling efficiency in modified or upgraded turbo applications. It opens at a lower temperature than standard thermostats, allowing coolant to flow through the engine sooner to reduce and maintain cooler engine temperatures. This thermostat is specifically designed for 1989-1993 Dodge Ram trucks with the 5.9L Cummins engine.

Fitment

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Specifications

BrandMishimoto
Part NumberM00C MMTS-RAM-89L

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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