Internal combustion engine cooling system

A cooling system for an internal combustion engine 104 comprises a first high temperature cooling circuit 100 coupled to an engine, for cooling the engine, and a second low temperature cooling circuit 102 coupled to a plurality of devices 118, 120,122, 124, for cooling the devices. The second cooling circuit includes a plurality of radiator segments 116a, 116b, 116c, 116d. The coolant circulating in the second cooling circuit exits the radiator segments as different temperature coolant streams for cooling the different devices. The first cooling circuit may include a radiator 108 positioned in a common stream of cooling air with the radiator segments. Preferably, the coolant flowing in the first circuit is isolated from the coolant flowing in the second circuit, where each cooling circuit includes a coolant pump 106, 114. The second cooling circuit may comprise a bypass line 128j to allow the coolant to bypass the radiator segments. Each cooling circuit may be used to cool an exhaust gas recirculation (EGR) cooler 110, 124.