I have a 2008 Grand Caravan with a 3.8. It is losing antifreeze. It has a new water pump, and there is no evidence of it leaking. That is until it is topped off. Then a few days later I find a puddle under it on the driver's side under the radiator. For example, my wife took our kids to school yesterday morning. It's about a 10 minute round trip.Other than that, the van didn't move at all yesterday. This morning she came out to find the picture below. The coolant was topped off on Friday. this was four days later. I have no idea what is going on. I'm wondering if there is a crack in the radiator and it leaks out until it's below the crack. The when it heats up (we don't drive it a whole lot) the expansion of coolant lets it leak from the crack again. I don't know. I'm at a loss.

 

I would inspect both of the radiator end tanks...if you see and dried red residue.it needs a rad

 

You can also rent a cooling system pressure tester from a parts store.