My sister has a "96 Mustang and it keeps losing antifreeze and over heating. We have monitored it for several weeks and have never seen any leakage on the ground. She has had the thermostat changed out with no luck. She fills the resevoir about every 2 days. Any ideas? Thank you in advance.

 

Try to look at the intake gaskets and check the exhaust to see if it's smoking at all. Check the oil for milkshake too.

 

I just had the same problem. Did you buy a fms thermostat? I bought autozone brand and it was worse then the old one and didnt work.

 

I had a similar problem and it turned out to be my heater core. I just by passed it

 

Really, because I picked up a 180* from autozone, don't remember if it's their own brand, but it works just fine.