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Mishimoto 89-93 Dodge 5.9L Cummins 87.5C High-Temperature Thermostat

SKU: MISMMTS-RAM-89H

Thermostats, Mechanical

MM Thermostats...

Mishimoto 89-93 Dodge 5.9L Cummins 87.5C High-Temperature Thermostat

SKU: MISMMTS-RAM-89H

Thermostats, Mechanical

MM Thermostats...

A$136.72
Available from MFR. This item is available from the manufacturer's distribution centre. The dispatch timeframe shown is an estimate based on historical order processing and release times for this part. This item is not held in our own warehouse, and actual dispatch timing may vary depending on manufacturer workload and logistics at the time of ordering.
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Description

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.

Product Overview

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 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.


Features and Benefits

  • Higher activation temperature restricts coolant circulation for a longer time, providing quicker engine warmup
  • Ideal for cold climates
  • Includes thermostat and high-quality replacement gasket

Product Details

Description:Mishimoto 89-93 Dodge 5.9L Cummins 87.5C High-Temperature Thermostat
Install Difficulty:2
Part Number:misMMTS-RAM-89H
Prop 65 - Short Label:WARNING: Cancer and Reproductive Harm - www.p65warnings.ca.gov
Prop 65 Y/N:Y
SellingPoint01:Direct fit for 1989-1993 Dodge Ram with 5.9L Cummins
SellingPoint02:Higher activation temperature restricts coolant circulation for a longer time, providing quicker engine warmup
SellingPoint03:Ideal for cold climates
SellingPoint04:Includes thermostat and high-quality replacement gasket
SellingPoint05:Mishimoto Lifetime Warranty
SellingPoint06:N/A
SellingPoint07:N/A
SellingPoint08:N/A
SellingPoint09:N/A
SellingPoint10:N/A
SellingPoint11:N/A
SellingPoint12:N/A
SellingPoint13:N/A
SellingPoint14:N/A
SellingPoint15:N/A
TechSpec 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
TechSpec Chassis Codes:D/W Series
TechSpec Engine Codes:6BT
TechSpec Includes:(1) Mishimoto Thermostat--(1) Thermostat Gasket--Mishimoto Lifetime Warranty
TechSpec Mishimoto Activation Temperature (F):189.5
TechSpec Note:N/A
TechSpec OEM Activation Temperature (F):180

Part Type

Engine Coolant Thermostat

Data: v4.2 - Upd: 2026-10-13 18:11:14

Features

  • Higher activation temperature restricts coolant circulation for a longer time, providing quicker engine warmup
  • Ideal for cold climates
  • Includes thermostat and high-quality replacement gasket

Specifications

Product Attributes - Brand
Mishimoto
Product Attributes - Manufacturer's Part Number
MMTS-RAM-89H
Product Attributes - Part Type
Thermostats, Mechanical
Product Attributes - Product Line
Mishimoto Thermostats
Product Attributes - UPC
840197702246
Product Attributes - Opening Temperature Rating (degrees F)
189 degrees F
Product Attributes - Thermostat Flow Rate
Standard-flow
Product Attributes - Gaskets Included
Yes
Product Attributes - Thermostat Material
Copper/Stainless steel
Product Attributes - Quantity
Sold individually.

Reference Information

Brand Name/s Mishimoto
StreetFX SKU misMMTS-RAM-89H
SFX Item ID 4050544
Supplier Item Code 4050544
Manufacturer SKU MMTS-RAM-89H
Manufacturer UPC 840197702246
Alternative References MIMMMTS-RAM-89H, MIO-MMTS-RAM-89H, 5.9L, 87.5C

Compatibility

Application Data
  • MakeDODGE
    ModelD250
    SubmodelBASE
    Beginning Year1989
    Ending Year1991
    Engine TypeL6
    Liter5.9
    CID359
    Engine Size5.9L/359
    Engine FamilyCummins diesel inline 6-cylinder
    Engine VIN Code8
  • MakeDODGE
    ModelD250
    SubmodelBASE
    Beginning Year1991
    Ending Year1993
    Engine TypeL6
    Liter5.9
    CID359
    Engine Size5.9L/359
    Engine FamilyCummins diesel inline 6-cylinder
    Engine VIN CodeC
  • MakeDODGE
    ModelD350
    SubmodelBASE
    Beginning Year1989
    Ending Year1991
    Engine TypeL6
    Liter5.9
    CID359
    Engine Size5.9L/359
    Engine FamilyCummins diesel inline 6-cylinder
    Engine VIN Code8
  • MakeDODGE
    ModelD350
    SubmodelBASE
    Beginning Year1991
    Ending Year1993
    Engine TypeL6
    Liter5.9
    CID359
    Engine Size5.9L/359
    Engine FamilyCummins diesel inline 6-cylinder
    Engine VIN CodeC
  • MakeDODGE
    ModelW250
    SubmodelBASE
    Beginning Year1989
    Ending Year1991
    Engine TypeL6
    Liter5.9
    CID359
    Engine Size5.9L/359
    Engine FamilyCummins diesel inline 6-cylinder
    Engine VIN Code8
  • MakeDODGE
    ModelW250
    SubmodelBASE
    Beginning Year1991
    Ending Year1993
    Engine TypeL6
    Liter5.9
    CID359
    Engine Size5.9L/359
    Engine FamilyCummins diesel inline 6-cylinder
    Engine VIN CodeC
  • MakeDODGE
    ModelW350
    SubmodelBASE
    Beginning Year1989
    Ending Year1991
    Engine TypeL6
    Liter5.9
    CID359
    Engine Size5.9L/359
    Engine FamilyCummins diesel inline 6-cylinder
    Engine VIN Code8
  • MakeDODGE
    ModelW350
    SubmodelBASE
    Beginning Year1992
    Ending Year1993
    Engine TypeL6
    Liter5.9
    CID359
    Engine Size5.9L/359
    Engine FamilyCummins diesel inline 6-cylinder
    Engine VIN CodeC

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