A heat exchanger comprises a shell formed from two joined-together shell members. Each shell member includes a tube plate that is integral with each respective shell member and that defines an axial end of the shell member. The shell members are joined along respective open ends. A plurality of tubes is disposed within the shell, and the tube ends are connected with the respective tube plates. A baffle is disposed within the shell and directs the path of coolant flow therein and over the tubes. One shell member includes a fluid inlet and the other a fluid outlet for directing coolant into and out of the shell. The heat exchanger includes an inlet manifold connected to one end of the shell and an outlet manifold connected to an opposite end of the shell.