Abstract: An improved end tank-to-header joint is disclosed. An end tank is formed with a flange portion that has at least one groove therein. A gasket having a predetermined cross-sectional shape is provided with at least one tongue portion that is adapted to engage the groove in an interference fit, thereby integrating the gasket with the end tank. A header is crimped to form a channel. The channel has a shape the corresponds to the shape of the gasket, such that the gasket is fully seated within the channel. A distal end of the header is then crimped around the flange of the end tank to ensure a fluid-tight seal at the joint.