hi, firstly i just noticed another similar thread, but think this is a slightly different case and didnt want to thread jack... my bro has been driving 70 miles each way to work , so 140 miles a day, for about 2 weeks, close to 900 miles a week, and went through 3 or 4 water tanks in them 2 weeks, , thers no signs of leaks, the temp gauge never goes above 90 once warm, theres also no smoke or water coming from exhaust, he had the car about 6 months prior to this and has never noticed anything before,,,, could this simply be due to the amount of miles he was doing? car has done about 145,000