Mishimoto 2003-2007 Dodge Ram 5.9L Cummins Replacement Transmission

This Mishimoto performance cooler is a direct-fit upgrade for 2003-2007 Dodge applications covering Ram 1500, Ram 1500 ST, Ram 2500, Ram 2500 ST, Ram 2500 TRX4. It replaces the weak points of the stock part with stronger materials and better flow or cooling so heat, boost and abuse stay under control on street and track duty. AutoTalent lists verified US-market fitment in the table below.

Why upgrade

The factory transmission oil cooler on your 2003-2007 Dodge Ram 5.9L Cummins is a liquid-to-liquid cooling unit, utilizing the engine's cooling system to cool the transmission fluid during warm outside temperatures and warm the fluid during cold outside temperatures. This design is tried and true, and it works. Until it doesn't. Mishimoto engineers these kits around real chassis packaging, so hoses, coolers and adapters line up without fabrication on the listed years. Follow the published torque specs and install guide, reuse sensors where instructed, and confirm clearances if you run other supporting mods. Every unit ships with the Mishimoto Lifetime Warranty for as long as you own it.

Features

• Direct fit for 2003-2007 Dodge Ram 5.9L Cummins
• Includes new powdercoated bracket and brass fittings for easy installation
• Durable, corrosion-resistant aluminum construction
• Equivalent to OEM specifications for fit and function
• Replaces leaking or failing factory transmission oil cooler
• Utilizes all factory lines and hardware
• No modification required for installation

What's Included

• (1) Replacement Transmission Oil Cooler
• (1) Bracket
• (2) -8AN Fittings
• Mishimoto Lifetime Warranty

Specifications

Fitment Notes

Verified against Mishimoto US applications and dealer listing for 2003-2007 (8 rows). Years extended to 2027 where the US model remains in production.

Vehicle Fitment