I don't know wtf is going on here. My truck has gone through quite a bit of coolant. I filled up the radiator (it was pretty dang low) and resivour(sp) like 3 weeks ago and now there isn't anything left in the res. The engine temp is fine, if anything it's running a little cool, and I'm not noticing any power or mileage differences, so does this put a blown head gasket out of the question? I haven't smelled any coolant and I haven't noticed any fluid puddles or anything.