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Vehicles you shop for show up here. Pick one in the Shop By Vehicle bar below.
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Fits 1989 to 1993 Dodge D250, D350, W250 and 1 more model. See every vehicle
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 (189.5F) compared to the factory thermostat (180F). By raising the activation temperature, coolant flows through the system later, promoting quicker engine 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.
Warranty: Lifetime Warranty
| Year | Make | Model | Submodel | Engine |
|---|---|---|---|---|
| 1989 | Dodge | D250 | Adventurer, Base, Club Cab, Custom | |
| 1990 | Dodge | D250 | Adventurer, Base, Club Cab, Prospector | |
| 1991 - 1993 | Dodge | D250 | Adventurer, Base, Club Cab, Custom, Prospector | |
| 1989 - 1993 | Dodge | D350 | Base, RD | |
| 1989 - 1993 | Dodge | W250 | Base | 5.9L 359 I6 |
| 1989 - 1993 | Dodge | W350 | Base | 5.9L 359 I6 |