Having this issue right now with my Quest. There's a 4 inch piece of coolant hose that goes to the oil cooler. Replaced the hose 2 years ago with OEM but don't remember what happened to the OEM spring clamps, so I just used some worm clamps. With the cold weather, it has started leaking out of one side, and one side only, and only leaks overnight when it gets really cold. Replaced the hose with bulk hose and a new worm clamp and it's doing the same thing. Leaking out of one side, only overnight after it gets very cold. Went back to the dealer and got an OEM molded hose (again) and two OEM spring clamps for $11 total. Have yet to replace it, but everywhere else I've ever used the spring clamps, they are bone dry. Starting to hate worm clamps.