Mishimoto Dodge Ram 5.9L/6.7L Cummins Transmission Cooler 2003-2009

The Mishimoto transmission cooler for the 2003-2009 Dodge Ram 2500/3500 5.9L and 6.7L Cummins is a direct-fit, stacked-plate upgrade with a massive 212% greater core volume and 244% greater fluid capacity than the stock cooler. It also solves a common failure point: where the factory thermostat fails closed and returns hot fluid to the transmission, Mishimoto's thermostat is fully serviceable through a port at the top of the cooler and can be easily bypassed for constant cooling. Replacement thermostats are available separately.

Specifications

This part fits:

Shipping

• In-stock orders placed before 3 PM EST ship the same day — everything else ships within 24 hours.
• Standard, expedited, and overnight options at checkout.
• Oversized items ship by freight and take longer.
• Backordered items ship as soon as stock lands — contact us for lead times.
• International orders: prices do not include VAT, duties, or import fees. Your country charges these at import and they are the buyer’s responsibility.

Returns

• 30-day returns on new, uninstalled items in original packaging with all hardware.
• Standard returns: 8% restocking fee, buyer pays return shipping. Both waived if the item is defective or we made the error.
• Installed or used parts can’t be returned — confirm fitment before you install.
• Special orders and custom items are final sale.
• Email us for return authorization before shipping anything back.

Full details: Shipping Policy · Refund Policy