...is low any ideas why? I fill it before we leave, and its a 2 1/2 hour trip and about half way, it tells me my coolant is low, and when i checked it it was all gone. It doesn't use it nearly as much when we are in town driving and there is never a puddle under the car. I use 50/50 coolant, could that be why? Or is there a leak somewhere I can't see? I know my car can't be using it, but I also have a 1990 honda civic and it uses coolant like that and I just add water in the summer time and its fine. I tried using some water in the jeep but could the water be just evaporating?