original BMW(not just X5s) water pumps typically fail between 60,000-80,000 miles - due to plastic vanes - some last 150,000+, some less than 50,000 - if you are taking it apart, then change the pump & thermostat (& gaskets) - it is less expensive to do it all at once - how are the belts??? - I had them done the same time

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Mark _______________________________
2001 X5 4.4i topaz blue/sand Sport, complete Dinan S2 , hitch, V1, tint, BSW Stage 1, Alpine INA-W910BT
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