gradually overheats on long drive no coolant is missing fan belt is quiet ... does not appear to be slipping turning on interior heater with fan brings temp down ( i have only seen water pumps fail by leaking and screeching ) What might it be ? How can I test ? 99guspuppet --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .