One of the rear coolant hoses was cracked. It was dry and brittle. Only reason I found out it was the hose was that I took a 40 minute high way drive and my temperature sky rocketed. Stopped at a gas station as soon as I could. When I pulled in there was steam spewing out from under the hood. By the looks of it, the hose has been that way for a long time, the drive just forced enough coolant to leak out for it to overheat. Lucky me, I was 40 minutes AWAY from the house. Had to wait an hour for help to arrive.