I have a 1996 Subaru Legacy 2.5 L EJ25D that overheats when the thermostat is in place but doesn't when the thermostat is not in place. The coolant seems to be forced into the overflow tank and usually cool not hot, the upper hose running from the engine to the radiator is really hard and really really hot the radiator itself tends to be relatively cool. The thermostat is new and it is from Subaru the coolant is Subaru coolant, there is no smell of exhaust in the Coolant just sweet smelling like it's supposed to, and there are no bubbles in the overflow tank. However I can't seem to get more than 10 minutes away from the house without it overheating these days. Any and all suggestions are welcome thank you very much have a good day.