Replaxed Water Pump, Thermostat, Housing, Radiator cap and..

[Hogitall]

..it's using water from the overflow tank to the rate of one overflow tank per day (20-25 miles of driving in mixed in town and highway driving and it's not leaking water/coolant anywhere that I or two other fairly car savvy friends can see. It smells hot but the gauge just goes up about 1/3 or a bit more of the range of the gauge. Of course I keep water/coolant going in it almost daily so perhaps it doesn't get a chance to really over heat. It's got 306k miles on it that were all but 25k put on by myself. 1998 Explorer, 4.0 SOHC 2 wheel drive, automatic transmission, A/C, .... 4 door.....I changed the factory Stereo/CD player out last year ...so don't even go there... ;-)
Any help would be greatly appreciated. Sorry if this is kind of a repeat...I don't think so though. Figured the CD player part would make it unique. *ducks*

 

[Rarestace]

My old car had a similar problem where it would use water like crazy and for like 6 months i couldn't figure it out so i had to add water everyday it turned out i had a small crack in the radiator and it would only leak when the car would cool down. so i would suggest you give your radiator a good looking over

 

[bobflood]

Make sure that the plastic overflow tank itself is not leaking.