I have a 2002 Ford Explorer that has been running well up untill the past couple of days. It has 165K miles, I just got a lot of regular maintanence done on it. 2 days ago I noticed it smelled hot and when I checked I realized the coolant reserve was empty. I put more coolant into it but by the time I got home the reserve was empty again. Over the past 2 days I've put 7 additional galloons of fluid into it but there is no obvious leak. There is no moisture under the car immediately after starting it, immediately after turning it off, or in the morning after it has sat. No hoses appear to be wet but the fluids keep vanishing. If any one knows what could be wrong I would appreciate some help.