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Vehicle Info NeededMISHIMOTOPART NUMBER: 690-MMTS-RAM-89H
MMTS-RAM-89H Thermostat High-Temp Dodge 5.9L First-Gen Cummins 1989-1993
$6495
Ships on 09/14/2026
Lowest Price GuaranteeThermostatHigh-Temp Dodge 5.9L First-Gen Cummins 1989-1993
Mishimoto MMTS-RAM-89H Features:
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 high-temperature thermostat for the 1989-1993 5.9L 12v Cummins. This Mishimoto thermostat activates at a higher temperature (189.5°F) compared to the factory thermostat (180°F). By raising the activation temperature, coolant flows through the system later, promoting quicker engi ne warmup. The Mishimoto high-temperature thermostat is ideal for vehicles in cold climates, where rapid warmup and quicker in-cabin heat is vital. This thermostat includes a high-quality replacement gasket and our signature Mishimoto Lifetime Warranty.- Higher activation temperature restricts coolant circulation for a longer time, providing quicker engine warmup
- Direct fit for 1989-1993 Dodge Ram with 5.9L Cummins
- Ideal for cold climates
- Includes thermostat and high-quality replacement gasket
- Mishimoto Lifetime Warranty
Part TypeThermostat
BrandMISHIMOTO
Package Height2.5
Package Width2.5
Package Length2.5
Weight0.09 PG
Part CategoryPerformance Parts
Part FitmentDirect Fit
Vendor Part NumberMMTS-RAM-89H
Package Qty1
Package TypeEA
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Some parts are not legal for use in California or other states with similar laws / regulations
