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Mishimoto MMTS-RAM-89L Low-Temperature Thermostat for Dodge Cummins - 5.9L 1989-1993

(1989-1993 Dodge W250; 1989-1993 Dodge D250; 1989-1993 Dodge W350; 1989-1993 Dodge D350)

Part of: Mishimoto Low-Temperature Thermostat for Dodge Cummins

Other options in this family: Mishimoto MMTS-RAM-99L Mishimoto MMTS-RAM-94L

Manufacturer

Picture for manufacturer Mishimoto

Part Number

MMTS-RAM-89L
8 reviews
Sale Price

$64.95

Estimated ship date Wednesday, November 25

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Product Details

The Mishimoto MMTS-RAM-89L low-temperature thermostat is engineered specifically for 1989-1993 Dodge Ram trucks equipped with the 5.9L 12-valve first-gen Cummins diesel engine. This performance thermostat activates at 174.2°F, compared to the factory thermostat's 180°F activation temperature, allowing coolant to flow through the radiator sooner for improved temperature management.

Key Features:

  • Lower activation temperature (174.2°F vs. 180°F stock) for enhanced cooling efficiency
  • Ideal for high-performance applications, heavy towing, and warmer climates
  • Direct-fit replacement for 5.9L 12v Cummins diesel engines
  • Includes high-quality replacement gasket for proper installation
  • Backed by Mishimoto Lifetime Warranty

By reducing coolant operating temperatures, this low-temp thermostat helps maintain optimal engine performance during demanding driving conditions. The earlier coolant flow reduces the risk of overheating and helps protect engine components during extreme use. Perfect for enthusiasts who demand maximum reliability from their first-generation Cummins diesel.

Products specifications

Fits

1989-1993 Dodge W250; 1989-1993 Dodge D250; 1989-1993 Dodge W350; 1989-1993 Dodge D350

Prop 65

WARNING: Cancer and Reproductive Harm - www.p65warnings.ca.gov

TechSpec Mishimoto Activation Temperature (F)

174.2

TechSpec Includes

(1) Mishimoto Thermostat--(1) Thermostat Gasket--Mishimoto Lifetime Warranty

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

Install Difficulty

2

TechSpec Engine Codes

6BT

TechSpec OEM Activation Temperature (F)

180

TechSpec Chassis Codes

D/W Series

Very easy to navigate, easy to find parts, easy to order.

SO FAR SO GOOD

The price was great and order/checkout simple. Thank you, Jim

Easy to order. Frt a little high.

Connectors arrived in this morning's mail. Took a little longer than expected, but order was filled and delivered. I would buy from them again.

Simple to order. Best price.

Amazing product and fast shipping! My purchase was exactly what I was looking for! Thank you!

Was very pleased with my order.

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