When I used to drive trucks, we would have the same problem like Joe said. Our Volvos were notorious for leaking antifreeze from the lower hose to radiator connection when it was cold out.
It is possible to tighten standard hose clamps too much. They pinch the hose and don't apply even pressure. I like dual wire hose clamps. they seem to do a much better job.
http://www.emwardfastenings.com/double-wire-clamps.html
