I had the same problem 2 weeks ago
got truck back from service dept. working on radio trouble, noticed an oily spot on center arm rest. I thought it was just the tech guys not being clean, next day with a/c on high I start getting hit with what seems like condensation, call the dealer they say they've never heard of that and to bring it in on monday morning(It was 5:55 friday eve). 20 min. later I've got a pool of coolant in my passanger side floorboard.
It's fixed now but still has a faint coolant smell mostly when you first turn on the air.