The heat exchanger is used to transfer heat from the engine oil into the coolant. Oil is delivered to the heat exchanger via a hollow centre bolt, after which it flows around the end tank and into the heat exchanger core, where it is circulated. Coolant is pumped around the outside of the heat exchanger core to cool the oil. The cooled oil then exits the heat exchanger and flows to the oil filter. An additional benefit of the heat exchanger is that, as the engine coolant reaches its operating temperature more quickly than the engine oil, the oil is heated by the engine coolant at lower engine temperatures; this allows the engine oil to reach its optimum operating temperature more quickly, thereby helping to improve engine oil life, reduce exhaust emissions and reduce engine wear.