I don't think I have heard my fan ever turn on. I have a 91 wagon with 91k miles. It overheats when I drive it. I replaced the thermostat with one from my 97 ex but so far it has changed nothing. I will stay at the right temp with the heat on when I putz around town, but will overheat with heat on on the highway after a while. not sure what the problem is so any help would be appreciated.

 

upperhose gets hot and lower hose stays cold.