jhawk

Thanks for the responses guys! The last time I had my coolant changed was January of 2010 when I had the the radiator replaced and the 100,000 mile service done. I do have an after market thermostat installed. Not sure if it was a true overheat, but the gauge climbed into the red, but I did not lose any coolant either if that helps. It was not snowing at the time. Not sure about the radiator cap, but maybe it was replace last year when the radiator was replaced. Please elaborate on the clogged bypass or heater core? All insights are appreciated! Justin

I have a 2001 Subaru outback limited edition with the 2.5 liter engine and it just recently overheated. I was about 3hrs into a 6hr drive traveling at interstate speeds and the outside air temperature was 15 degrees F. I am baffled, because this exact same thing happened to me last year while I was traveling to the same place, almost at the same spot on the interstate, and the outside air temp was roughly the same. The car doesn't overheat during the summer and I have driven comparable distances. So far I have had several mechanics run compression tests on it, and the mechanics have said that it doesn't appear to be a headgasket problem; the thermostat has been checked and appears fine, and the radiator was replaced when I had the 100,000 mile maintenance done to it. Any suggestions would be appreciated! Thanks, Justin