The factory expansion tank on your 2019+ Ram 6.7L Cummins is a weak point in an otherwise durable cooling system. Made from plastic, the stock tank becomes brittle over time and is prone to cracking, discoloration, and internal degradation after thousands of heat cycles. Mishimoto’s aluminum expansion tank is built to solve that problem before it starts. Its TIG-welded construction holds up under high temperatures and heavy use, while internal baffles prevent coolant starvation and reduce the risk of air pockets that can harm engine cooling.

To make installation simple, this expansion tank fits directly in place of the factory unit and does not require draining the entire cooling system. No specialty tools are needed, and all necessary provisions for factory sensors are included. That includes an OEM-style level sensor that allows the truck’s stock low coolant warning system to function exactly as intended.

Beyond durability and ease of install, this expansion tank gives your engine bay a cleaner, more finished look. The Mishimoto expansion tank is available in either micro-wrinkle black or a natural finish, for easy customization through powder-coating, anodizing, or hydro-dipping. It replaces the aging plastic tank with something built to last and designed to look good doing it.

Like all of our products, this expansion tank is backed by the Mishimoto Lifetime Warranty.